You can combine closely related activities onto one Schedule C. If your businesses were delivering food and fixing computers, they would clearly be separate Schedule C's, in this case it's less obvious, you could argue that using your car to pick up and deliver food is pretty much the same as using your car to pick up and deliver people.
It makes little difference, won't affect your tax burden, and you likely would never face scrutiny if you combined them or kept them separate.
I would likely file two schedule C's as they feel different enough to me and for my own records I'd want to be able to consider each individually. It does affect some informational items that they collect. Lines A and B on Schedule C are used to describe/categorize the nature of your business. The IRS has a business/professional activity code that specifically mentions ridesharing services:
485300 - Taxi, limousine, & ridesharing service
While food delivery might better fit under:
492000 - Couriers & messengers
Perhaps there's a better code for that one, I didn't spend much time looking.