It's a personal choice on topping, some people don't top, but then get more popcorn buds on the rest of the plant and a nice main kola.
Usually people top at least once or twice, and that just helps Bush out the plant more, it really depends on your amount of space.
If you want to try and Scrog, then top it 4 or 5 times, and lst the tops over, FIM it out underneath and you'll have a nice screen full of decent kolas, and no little popcorn buds.
It depends so much on light and space and time. The more tops, generally the more work you will have. If you have nice strong lights then top it once or twice and leave it. Your light should have enough penatration to give you bud all the way down.
If it's a weaker light, or fluorescent, then top it lots and FIM it out underneath, it will have a Nice canopy to collect all the light.
Experiment, cannabis is resilient.