[¯|_(ツ)_|¯]

It sounds like you are a mature adult who is doing a lot to support yourself. You should be proud of yourself for doing all that you do! It also sounds like your mom is having a difficult time accepting the reality that her children are starting to grow up and don't need her as much anymore. It's hard for some parents to come to terms with the fact that their children aren't the little kids that they once were and that they're becoming their own people.

Do you think when your mother tells you all of the reasons this won't work that you can tell her you need to be allowed to make mistakes and fail sometimes, because that's how you learn and grow? No adult gets everything right but if you don't put yourself out there you'll never be able to see what works and doesn't work for you. I'm not saying that you are going to fail, because it does seem like you have a good head on your shoulders, I'm just saying that every person out there has things that just don't go right, but it was still a necessity for them to experience those things. Maybe you can explain that to her?

You can also tell her that IF things don't go right, you'll consider commuting or living back in the dorms, but you really want to get this new experience first and at least give it a chance to work. Instead of "what if my daughter fails," turn it into "what if my daughter succeeds?"

If you think the issue is what I mentioned above about your mom not accepting her children are getting older, maybe you can make some compromises with her like being sure to video chat with her on your day off for a while so she can still talk to you.