Welcome to the forum. You've come to the right place for all your questions about building your first motorized bicycle. Try the search feature for your questions and if you don't find an answer then don't hesitate to ask. There's plenty of knowledge here to help you through to a successful build.
And watch out for that guy called Goat Herder. He's just an old guy who hangs around here from time to time; doesn't know much but he's a friendly old sort