I've had the same surgery (I presume... calcaneal osteotomy?) and two others on my ankle.
I was in a lot of pain afterwards... so take all the painkillers they offer!
If you have a cast, you can ice through the cast if you have a thick gel ice pack, or behind your knee.
Try to raise your foot above the level of your heart for most of the time - use lots of cushions or put your leg along the back of the sofa. This helps prevent swelling and thus pain.
I never had a knee walker but would have loved one as I struggled with crutches. If you have someone to push you, a wheelchair is good for outings.
Get a litter picker (grabber) to help pick up all the things you will inevitably drop on the floor.
Consider a raised toilet seat and or grab handle in the loo (you can get ones that stick to the wall with suction pads) - it's surprisingly hard to get on and off the loo (changing sanitary protection is an added joy!).
Get a cast cover for the shower and put a garden chair in there if you have room, if not get a shower stool. Showering on one leg is, well, impossible.
Agree with PP re cross body bag to carry stuff around, office type chair to move around house/do stuff in kitchen, set up area with everything you need near your spot on the couch.
Recovery is lonely and boring so try to arrange outings, get friends or family to visit... and come here and let us know how you're doing!