I'm just wondering what people generally do to start making a map for a game. I made an 2 arrays and styled it so that it's in a row/column grid format but, I'm wondering if that's the best way to go about it?

My brother is good at 3D modeling and he said he can convert them to web or something. Do I need to use some type of game engine to accomplish this?

Do people just create their own engine if one is actually needed?

Other than PHP to store database values for items, login info, etc. etc. Will I need to use any other languages?

Is their anymore questions I should be asking?