Hi there and welcome to the site!
So, sounds like your LO has been cosleeping from the start and you'd like him to learn to sleep independently in his own room.
A few thoughts/questions:
-where does he nap? does he have a bed or crib in his room?
How much water does he drink at night? just a small sippy cup or bottles?
I think a good place to start would be to get the book, "the Baby Whisperer Solves All your Problems". People here refer to it as TBWSAYP- it's a great book and there are some case studies of older toddlers learning to sleep independently.
I'll have to think a bit on this, but maybe there are more folks with ideas. Sounds like you both must be chronically tired and I admire you for going through school while being a single parent!
I think some people put a small blow up mattress on their child's floor and sleep seperately in the kid's room as step one, then slowly move mattress closer to the door each night, then after a week or so, place mattress outside the room... etc. etc..
I'll try to find more details for you.