I can't click on my Sims or make them interact with each other in The Sims 4

@n0treece  As a test, please try playing in a clean user folder.  Move the entire Sims 4 folder out of Documents > Electronic Arts and onto your desktop, and when you launch the game, a clean folder will spawn with no content.  (Your saves and other content will be intact in the folder you moved but temporarily not read by the game.)  Don't add anything to the new folder yet; just start a new save and see how the sims behave.

If the new save is fine, copy one of your existing saves to the new Sims 4 folder and test that too.  Let me know how it goes.