My recommendation would be to have a thorough assessment by a licensed physical therapist. There are many factors to take into consideration when determining a treatment plan…from the type of surgery performed, weight bearing restrictions, strength and range of motion deficits, etc. Also, consult with your surgeon prior to resuming activity,

You should check with your physician as patient and procedural issues may dictate when certain activities can begin. That noted patients can often begin walking the day of or the day after hip surgery nowadays.

We'd need to know what kind of surgery, if it's a fracture with hard wear fixation or hip replacement, and what the weight bearing status is, but in any event, being in bed for 3 months, you need to do some exercises to keep your muscles toned. I hope somebody did explain those exercises, also, contact your surgeon to see what the weight bearing status at this time is and then go from there.

That's completely up to your surgeon, so that's who you should be asking. But, based on what you said...complete bed rest for 3 months, it seems like you should be able to get back to exercising the day after your sentence is over. However, if they'll allow you to exercise the upper body in order to save whatever sort of cardiovascular fitness you still have, then you should get permission for that right now.

discuss this with your surgeon as there are many "hip bone" surgeries. 3 months of bed rest is a very long time and I am not familiar of any common surgery that recommends "bed rest" for 3 months

Once you are cleared by your Orthopeadic surgeon, then and only then seek the counsel of your local PT.