Is there a way to time stamp a photo taken with my iPhone 10?

I don't think there is a time stamp feature but you can always go on the photo, press 'Edit', and then the 3 dots in a circle at the top. Something called 'Markup' should come up. Press it and from there you can draw and edit your picture however you want. To add text, just press the '+' button at the bottom right and then press 'Text'. You can add the date there.

I hope this helps

Photos are automatically time stamped. Just open any photo and at the top you will see the date and time that it was taken.