Cut off first top flower?

A question from a fellow grower:

When the the first two flowers bloom on top do you cut off the top one and when do you know it’s time to cross plant

Are you talking about “cloning”? or topping your plant - if topping suggest wait till 4th -5th node- if you are going to clone take the clone from the middle of the plant were growth is strong. Cross-plant? (clonning- right)