The best option would be for him to file as independent, check the box No one can claim me as a dependent and claim his educational credit himself. He CAN claim his cell phone as business expenses for Door Dash business, even if he didn't have a home office; he still used it to communicate with customers. And yes, this income and expenses has to be reported on the Schedule C.
You can learn what else can be deductible for him here:
Filing Tax Returns for Delivery Drivers: Tips and Advice
