I’m changing over to the flex this year. I have a solid team that are A iq in triangle. There is no good time to change but I have a good freshman class that I want to run the flex. My ? Is Can I put my prac minutes into flex but run a triangle in the game since my starting lineup is all As at triangle? Thanks and if I do this will it affect them learning the flex..

You can and probably should run Triangle while practicing Flex. I don't believe it has any impact on how quickly your players learn the game new offense. You'll get an email from an assistant asking WTF you're doing but feel free to ignore him.