Sun light for marijuana plants

A question from a fellow grower:

how much sun light does a plant require?

Marijuana likes a lot of sun. As much as it can get. Seedlings and small plants need to be acclimated to the sun slowly. As far as how long or how much light versus how much dark to cause the plant to start flowering. It depends on how big you want it to grow before it starts to “bud” or flower. If you give it more than 12 hours of light a day it will continue vegetative growth and continue to get very bushy. If you give it at least 12 hours of uninterrupted darkness it will start to flower and create its “buds” or “nugs”.

So just to be crystal clear …
If I have a light that’s powerful enough to flower many plants… will that same light will be ok to use from seedling stage ?