I think probably the wisest course is to plan for the worst but hope for the best. It is extremely variable.

I had a really hard time with the chemo and right from week 1 of my treatments I was unable to work much because I was dealing with chemo-nausea. I was actually teaching an online course at the time that ran for the first five five weeks of the seven weeks I had my treatment. I would get on whenever I felt well enough to sit in front of the computer and do the grading but I was a less than really responsive teacher that semester. And the only way I manged at all was having something to puke in nearby as I worked--it would have been a disaster if I'd tried to work in a face-to-face kind of job during that time.

After, I was also pretty sick for about 5 months (then once I started feeling better, I started radiation for the breast cancer which I was fighting at the same time and that made me exhausted all over gain).

But I think I had a much harder time than many folks here --I hope your father has an easier time of it!

Nelie