You are so much younger than most of us that some things can be different. Yes get your legs and abdominal muscles strong.
Hospital stay is usually 5-7 days. Sometimes rehab, but you may not because of your parents being there for you.
There isn't laying around all day. You must get up and walk and increase that everyday.
Pain can be managed first with medication and then with things like heat packs and meditation.
I have gone through my last 3 surgeries on Tylenol and gabapentin. Not easy but it can be done. The advantage seems to be no effects from narcotics. It is tough at first but then so much easier.
You will be tired a lot and that is when you rest.
Good luck and it will get better
T10-pelvis fusion 12/08
C5,6,7 fusion 9/10
T2--T10 fusion 2/11
C 4-5 fusion 11/14
Right scapulectomy 6/15
Right pectoralis major muscle transfer to scapula
To replace the action of Serratus Anterior muscle 3/16
Broken neck 9/28/2018
Emergency surgery posterior fusion C4- T3
Repeated 11/2018 because rods pulled apart added T2 fusion
Removal of partial right thoracic hardware 1/2020
Removal and replacement of C4-T10 hardware with C7 and T 1
Osteotomy