How can i send jwt token to client after OAuth autherization?

I am trying to authenticate user with GitHub OAuth and for regular users i am using jwt tokens.

In my flow , the user press the button "Login with github" and after that by follow the Github docs - user redirect to github web for choose his account.

So this is my main code for my client side:

function SocialLogin(props) { 

    const githubAuth = async (e) =>{
        e.preventDefault()
        const githubOAuthURL = 'http://localhost:5000/api/oauth/github';
        let githubTab = window.open(githubOAuthURL, '_self');
        githubTab.focus();
    }  

  return (
    <div>
        <div className="right-box-inner"></div>
        <div className="wrap-buttons">
            <div className="signwith">Sign in with Social Network</div>
            <button onClick={githubAuth} className="social github"><i className="fab fa-github"></i>    Log in with Github</button>
        </div>
    </div>
  )
}

In my server side, the route "api/oauth/github" that the client asks for, is:

router.get('/github', async (req,res) => {
    try{
    res.redirect('https://github.com/login/oauth/authorize/?client_id='+config.get('githubClientId'))
    }
    catch(err){
        console.log(err.response)
    }
})

so after https://github.com/login/oauth/authorize/?client_id='+config.get('githubClientId') is exectued ,and the correcrly choose his account , the callback url as i defined in my app settings at githubaccount, executed:

router.get('/github/callback', async (req,res) => {
    const {query} = req;
    const code = query.code;
    try{
        if(!code)
          return res.status(404).json({msg : 'Autherization failed'})
        else{
          const gitAuthDetails = {
            client_id: config.get('githubClientId'),
            client_secret: config.get('githubSecret'),
            code: code
            
        }
          const headers = {
            headers: {
                'Content-Type': 'application/json;charset=UTF-8',
                "Access-Control-Allow-Origin": "*",
            }
          }
          const response=await axios.post('https://github.com/login/oauth/access_token',gitAuthDetails,headers)
          access_token=response.data.split('=')[1].split('&')[0]

          const userResponse=await axios.get('https://api.github.com/user',{ headers: { Authorization: 'token ' + access_token } })

          //Lets asssume that i store here a new user to my DB with the all github details e.g username, email ...
          // and create a payload for jwt.
          // Now i want to generate new JWT for the new user , and problem is here. to where i need send my token? 
          // there is any function in my client side that listening and waiting for response.
            jwt.sign(
                payload,
                config.get('jwtSecret'),
                {expiresIn:360000},
                (err,token) => {
                    if(err) throw err;
                    //What i need to do with my token?
                    res.redirect('http://localhost:3000/dashboard')
                }
            );


        }
    }
    catch(err){
    console.log(err)
    res.redirect('http://localhost:3000/login')
    }
})

So as I described in my code , I am stuck here with my token , and I want to send it to client side, and there store my token to localStorage.

some advices?