Some Questions About Cresties

Hello! So i’ve been looking into possibly purchasing a crested gecko so i’ve been trying to do some research before hand. But i feel as though no one has answered these questions yet. First of all, people say to feed the gecko 3 times a week (the powder water mixture: Repashy: Pangea) but no one has said like 3 days in a row or like every other day. Then also like how long does the mixture last? Do they eat it in one sitting? Also if you choose to offer insects then do you have to wait to give insects on the days your not giving the other food? Or substitute the powder water food for insects? Sorry so many questions and i’ll probably think of more later lol. But i’d really appreciate some help :)