Node JS session errors: express-session deprecated

When running my app.js I get this in the terminal:

express-session deprecated undefined resave option; provide resave option node_modules\admin-bro-expressjs\plugin.js:176:14
express-session deprecated undefined saveUninitialized option; provide saveUninitialized option node_modules\admin-bro-expressjs\plugin.js:176:14
express-session deprecated req.secret; provide secret option node_modules\admin-bro-expressjs\plugin.js:176:14
express-session deprecated req.secret; provide secret option app.js:34:5

this is what I have in my process.env :

SESSION_SECRET = "This is my final project of undergrad!"

when I try to load the page on localhost this is what I get so it won't let me see any of my webpage work:

secret option required for sessions
Error: secret option required for sessions
    at session (C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\express-session\index.js:200:12)
    at Layer.handle [as handle_request] (C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\express\lib\router\layer.js:95:5)
    at trim_prefix (C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\express\lib\router\index.js:317:13)
    at C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\express\lib\router\index.js:284:7
    at Function.process_params (C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\express\lib\router\index.js:335:12)
    at next (C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\express\lib\router\index.js:275:10)
    at SendStream.error (C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\serve-static\index.js:121:7)
    at SendStream.emit (events.js:315:20)
    at SendStream.error (C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\send\index.js:270:17)
    at SendStream.onStatError (C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\send\index.js:421:12)
    at next (C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\send\index.js:764:28)
    at C:\Users\lil_s\Downloads\Rich Internet Applications Spring 2021\EAZ6NEJsports\EAZ6NEJsports-master\node_modules\send\index.js:772:23
    at FSReqCallback.oncomplete (fs.js:183:21)

Here is app.js below in full as requested by Deepak on their comment:

const dotenv = require("dotenv").config();
const createError = require("http-errors");
const express = require("express");
const path = require("path");
const cookieParser = require("cookie-parser");
const logger = require("morgan");
const mongoose = require("mongoose");
const session = require("express-session");
const passport = require("passport");
const flash = require("connect-flash");
const Category = require("./models/category");
var MongoStore = require("connect-mongo")(session);
const connectDB = require("./config/db");

const app = express();
require("./config/passport");

// mongodb configuration
connectDB();
// view engine setup
app.set("views", path.join(__dirname, "views"));
app.set("view engine", "ejs");

// admin route
const adminRouter = require("./routes/admin");
app.use("/admin", adminRouter);

app.use(logger("dev"));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, "public")));
app.use(
    session({
        secret: process.env.SESSION_SECRET,
        resave: false,
        saveUninitialized: false,
        store: new MongoStore({
            mongooseConnection: mongoose.connection,
        }),
        //session expires after 3 hours
        cookie: { maxAge: 60 * 1000 * 60 * 3 },
    })
);
app.use(flash());
app.use(passport.initialize());
app.use(passport.session());

// global variables across routes
app.use(async(req, res, next) => {
    try {
        res.locals.login = req.isAuthenticated();
        res.locals.session = req.session;
        res.locals.currentUser = req.user;
        const categories = await Category.find({}).sort({ title: 1 }).exec();
        res.locals.categories = categories;
        next();
    } catch (error) {
        console.log(error);
        res.redirect("/");
    }
});

// add breadcrumbs
get_breadcrumbs = function(url) {
    var rtn = [{ name: "Home", url: "/" }],
        acc = "", // accumulative url
        arr = url.substring(1).split("/");

    for (i = 0; i < arr.length; i++) {
        acc = i != arr.length - 1 ? acc + "/" + arr[i] : null;
        rtn[i + 1] = {
            name: arr[i].charAt(0).toUpperCase() + arr[i].slice(1),
            url: acc,
        };
    }
    return rtn;
};
app.use(function(req, res, next) {
    req.breadcrumbs = get_breadcrumbs(req.originalUrl);
    next();
});

//routes config
const indexRouter = require("./routes/index");
const productsRouter = require("./routes/products");
const usersRouter = require("./routes/user");
const pagesRouter = require("./routes/pages");
app.use("/products", productsRouter);
app.use("/user", usersRouter);
app.use("/pages", pagesRouter);
app.use("/", indexRouter);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
    next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
    // set locals, only providing error in development
    res.locals.message = err.message;
    res.locals.error = req.app.get("env") === "development" ? err : {};

    // render the error page
    res.status(err.status || 500);
    res.render("error");
});

var port = process.env.PORT || 3000;
app.set("port", port);
app.listen(port, () => {
    console.log("Server running at port " + port);
});

module.exports = app;

If there is anything else you need me to provide to help, please let me know! Thanks in advance everybody!