What is the post-op like for a shoulder arthroscopy?

What are you having done specifically?

Torn supraspinatus stitch.
Then subacromial spur shaving.
Plus explore

A lot depend on the explore part. The fact they are exploring leaves many questions.

Anywhere between sore for two weeks to sore and limited movement + rehab for 6 months.

How do you do daily activities? How do you take a shower?
Surgeon said 6 weeks in sling and then 3 months of holding nothing heavier than a coffee cup.
How do you manage?

I can help you with one arm stuff. All this is dependent on where you work.

Elastic old man jeans or pants. I couldn't button, zip or buckle for 3 months.
Learn to wipe with your other hand. That way you can clean up the mess with your dominant hand as you learn.
Eating sucks. Using a fork with my left hand was hard, but you learn or you starve.
Typing with one hand is remarkably easy. Slows you down, but not bad.
I could still mow with one arm.
Boots/slides/loose tennis shoes, if you can't tie your shoes. If you have to lace your boots, one had it like below. Tie it before you lace them so it is just loose enough to get it past the last wrap.

Better hope you have an automatic car.
Just figure your good arm isn't going to get washed.
Polo shirts are your friend. If you must wear a button up shirt, you will probably need help.
Keep working out. I put on a harness and pulled a sled just about every day. Got boring as hell. kept lifting, too, on armed.
I'm bald and have a massive beard. I don't have to worry much about grooming. Blow dry the beard and brush it out.
Everything else is just an annoyance doing it with one arm/hand.