Best Way to Show Home Feed According to User Preference

I'm working on a startup where I need to show data according to user preferences. I successfully collect what user likes, dislikes, whom to follow, and other stuff, etc... Now I need to show the user data or you can say the Home Feed like how Reddit, Twitter, Facebook, and other Social Media Platform shows.

You may be saying that you get the posts of user preferences from the database and show it. But you see if a user following someone and the followee has uploaded three or four posts since the previous visit of my user. Now, this is where my first question arises.

1. Should I show all the posts one after another or show a couple of posts then insert a couple of different follower posts and later show the remaining post? 2. Another question if the above scenario is correct how do I randomize the user preferences and show them with proper pagination. Because I can't just load all the data to the website or app. This will cost me performance issues.

Thanks for your time.