He'll be fine. I've moved MANY times with cats, and the main thing is to set up a quiet room for the kitty first thing--do that before anything else. Then, by the time you get things set up and he can come out, he'll see that it's the same old stuff, same person, etc. and he'll be fine. Spraying some Feliway around helps a lot.
Re: keeping him indoors--it will be easier on him if you keep him indoors ALL the time, rather than only when you are not home. If you let him go out when you return home, he'll never get over wanting to go out, which may make him miserable when you're away and he's inside. You may also rarely see him if he's out when you're home and only in when you're away!
I have converted MANY cats from outdoor to indoor and honestly, it's not that hard. If you provide plenty of vertical areas for climbing and lounging (could be a cat tree, a window perch, shelves on the wall, a bookcase w/ some shelves cleared off, etc), toys, comfy beds, and a sunny window, most cats adapt in a matter of weeks. As long as you don't let him out at ALL, he will get used to it and be perfectly happy!
A bird feeder or 2 is a wonderful addition to cats' lives (and it's nice for the birds, too!). Put it outside a nice window w/ a perch or piece of furniture where the cat can sit, fill it up, and wait for the birds to find it. My feeders draw goldfinches, house finches, sparrows, tufted titmice, chickadees, and cardinals-- so it's nice for ME, too!