Going for surgery in 3 weeks

Went to cleveland clinic yesterday am scheduled for surgery the 6 of july after colonoscopy on the 30 of this month Dr wants to check everything out first he said the tumor is size of grapefruit but he thinks he can get it all out then in a few months biopsy my lung and go from there I dont understand why different DRS give so many different

answers but I heard cleveland was really good and the surgeon seems really confident
What I dont understand is when this all started my onc told me surgery wasnt an option now it is" talk about confusing I do trust my onc he sent me to cleveland when chemo stopped working just dont understand the reasoning But the good news is no more chemo hopefully ] any advice anyone has Im all ears or should I say eyes?

Sheri22