Tips for a long-lost android user

Kia ora!

I've been an ios user for 100 years at this point, but used to be deep in the android scene before then. I've just got an android for a work phone and am wondering what's changed in the last 10 years - what are your essential apps, settings, customisations? I've had a hunt around xda but can't seem to find much in the way of roms for my model (Samsung A04) - back in the day it seemed there was a thread for every device!

What do I need to know?