How long to plan for being out of work

I wanted to introduce myself and ask a question. I do not have a formal diagnosis of lung cancer, but have atypical cells. I am going to have a PET scan and I have a robotic assisted lobectomy coming up in September. These will be more diagnostic than my biopsy was.
I was hoping to get some insight as to how much time to take off from work for healing. My job is not strenuous at all and involves mostly sitting and talking.