Rewriting pagination with htaccess

I want to rewrite the pagination URL:

https://www.example.com/post?page=1&fsomething=1

to:

https://www.example.com/post/1/page=1

Here are some examples of my attempts to do so:

RewriteEngine On

RewriteRule ^(.*)/page=$ post?page=$1&something=$2 [L,NC]

and

RewriteRule ^(.+)/page/(\d+)/?$ $1?page=$2&something=$3 [L,NC,QSA]