You beat me by 1 minute! 5x5 is an excellent starter program. I've lifted for about 10 years and while I'm more in the advanced and intermediate lifting programs, 5x5 is my goto when I have a long hiatus in lifting. I'm definitely doing it once the COVID lockdowns are over.

Seems like this requires both physical space and equipment. Being stuck at home right now, what would be good enough alternatives for the exercises other than squats (perhaps with smaller dumbbells or with body weight)?

https://old.reddit.com/r/bodyweightfitness/wiki/kb/recommend... - maybe check out this program. I haven't run it myself, but I've heard a lot of people speak well of it.