How do I warn other about my trainer?

First and foremost, do you feel safe. Is this person making any threats of any kind, especially physical violence? And not just to you, people that you encounter as part of the job.

Things you have listed, make for a difficult environment. It is hard enough to learn, practice and hone skills in a good environment.

How long have you been in this training program?

 

Recording his abuse will help you document any claims.

 

Your choice is to ask for another trainer or finish with this trainer. Not getting training with backing is a clear factual shortcoming of your trainer. I would ask for another trainer if this one won't train you in backing. If the company says they cannot give you another trainer, keep your mouth shut and complete training with this trainer.

 

2 threads posted within minutes about the same topic. Maybe they should be merged?

"Super penny pincher I looked it up he’s a chronic underspender(needs counciling I looked it up) "
You looked what up? Twice?

The person is a slob and doesn't want to spend money. Got it.
Are you expecting him to pay for your stuff? Is that how he is under-spending?

I understand about not wanting to spend time in a pig pen or observe bad habits, and that might be the reason to go to your driver manager for an out.
The next trainer could be better or even worse, you never know.