New to the Sims 4. Timing question.

I'm new to the Sims 4, but got a deal on the game and pretty much have everything. Does your Sims' lives continue even when you're not playing them? I made two separate sims, had them live in the same neighborhood but in separate houses, and then sent one to college (Sam) and decided to play as the other (Joe) for a few days. When I went back to Sam, he was failing all of his classes! I assumed that the time at the university would be the same from when I left him. Do I have to be conscious of every Sim when I play showbox.tools/ speedtest.vet/!?!?

I did have Joe and Sam spend considerable amounts of time together. Does that make a difference?0