Age seems to really matter here, so with the preface I'm 42,
1. I was a side sleeper too, there really is no chance of sleeping on your side for ~10 weeks. I didn't like it but its not the worst of it...
2. I got a sponge on a stick for like $3. It was great. Highly recommend. Its hard to shower but its not getting out of bed hard

For the first week you should get use to the idea that a Nurse is likely neccesary to clean you in all regards.
3. Like most have said there are different levels. They will get you walking or standing up as soon as they possible can. A body at rest tends to stay at rest (Newton was a smart man)... The chest gym / strength rebuilding component is probably 10-12 weeks out. I didn't really get to *start* using my chest/pecks successfully until week 12. Your mileage may vary.
4. I'm a software engineer, started writing code on day 3, went a little too hard (1 hour) too early and had an anxiety / heart racing episode when I fell asleep sitting up. You'll be able to do it pretty early but don't over estimate your ability to situp straight in the first 2-3 weeks for too long at one time. I was coding 8 hours a day by week 4.
I highly recommend finding a psychologist for the first 12-16 weeks, it has weird (well documented) affects on your brain, more predominantly for people under 60. The severe depression and anxiety events went away (almost magically) after week 14ish, but my doctor gave me the advice to start early because its normal to happen but if it sticks around (rare) you've got the psychology sessions to help justify the necessary psychiatric help. Just having a stranger to talk to about the weird experience that OHS is, was really helpful, even if I was ultimately fine.