How to Get Instagram Graph API User Access Token From Server Side

Question

I'm trying to develop a web application to display Instagram media along with the metrics like comments count, likes count, etc, of a user registered in my application. Users need to signup using their email and password and after successful signup, there is a button to verify their Instagram account. Since there are two APIs (Basic Display API and Graph API), I can use Basic display API authorization endpoints to authorize users with my app. I have got no issue with that. But in order to get the user data like follower count, metrics of media, etc, I need to access the Graph API. According to the docs I need to implement a Facebook login to get the access token for that. But I don't wanna implement a Facebook login. I just want to grab the access token only from the server-side. Currently, I'm using the Graph API Explorer to get the short-lived access token and exchange it with a long-lived access token. Is there any way to do this from the server-side only? Without using Facebook SDK or without implementing Facebook login? I've read the Facebook docs but it's not helpful.