Once again, I think Josephine is right on target! I would only add, to consider your current physical condition, the better your current condition and overall health, the better I believe you will do.
My OS would not do a BTKR (for many reasons discussed before on this forum); I final talked him into doing one on 11/17, second on 12/1 (actually 8 and 6 weeks today??). My situation was complicated because I live in a two story house; my 1st, the RTKR replaced by "bad" knee, no problem I knew I still would have the "good" left knee, which always pulled me up the stairs and it would still be working fine, but the concern was what would I do when they cut out that good one! On about day 12th day I was able to use the new knee to pull myself up the stairs.
Today I am making the stairs normally and (almost) without the use of the banister.
I must also add that during this time I think I lost 2-3 weeks of rehab, not because of the knees, but because of secondary issues with meds etc. Unfortunately, during this time I could never do more than a half hour rehab a day else it would totally exhaust me and for the next two days,and then all I could do was to lay around the house.
So I have been to my GP to help correct the "side effects" problem and yesterday I went to back to work, at least it something to do.
In retrospect, "how would I do it if I had to do it again?" Exactly what I did! It has worked out perfectly for me. If I were about 60 years old and you ask me that question, I would probably have a great hesitation in my answer.
Keep in mind, no two people are alike, no two knees are the same.
Good luck, you'll be fine!