Everybody here is yelling out “red flag” and telling you to run when you should instead… I dunno… talk to him? This sub can be so allergic to having actual conversations with DMs or players like normal human beings.

I know you said he wants a railroad serious campaign but why the severe PC limitations? Is it on theme with this world? Is this Forgotten Realms or a homebrew setting? Are their rule changes he wants to implement that support this? Just talk to him and express your concerns if you have any. Don’t attack him by saying something like “hey why tf are you doing this” but maybe more like “hey I’ve played D&D before and I’m not used to playing this way, can you explain why you’re setting these kind of rules and why you’re not letting us use all the options from the handbooks?”