Hey I no longer have the DoorDash app on my phone and it charged me 10 dollars for a dashpass

Dashpass is a subscription based $0 delivery service. If you subscribed to this service, just removing the App from your iPhone doesn't cancel a subscription you agree to pay.

You need to cancel the subscription and this will explain how to do that --> Cancel a subscription from Apple - Apple Support

You can request a refund, but all sales are final and there's no guarantee you'll get a refund, especially if you just deleted the app believing that would end your subscription to this service. You can try this, but again, they may not approve a refund request --> Request a refund for apps or content that you bought from Apple - Apple Support

From what I see, this is not a subscription that is managed by Apple at all and would not appear when attempting to cancel the subscription in Settings on your device. To me this looks like a subscription that was made directly with DoorDash where you used Apple Cash to pay for the subscription. Using Apple Cash does not mean the subscription is managed by Apple, it is just a means to pay for that subscription. Those charges will continue until you cancel and you would need to do that with DoorDash, not Apple.

A quick look at the DoorDash website revealed steps to take here for cancelling a subscription where you subscribed with them directly. It can be done either within the app or on their website.

https://help.doordash.com/en-us/consumers/article/how-do-i-cancel-my-dashpass-subscription