If I erase all content and settings on an iphone?

And the new owner of that phone sets the phone up again using their own apple id etc my photos and videos that I take on my new phone are no longer going to go to that phone right because the icloud will no longer be on that phone right? Lol sorry if this is dumb but i have recently given my dad my old phone and i did something dumb with recording a video and immediately deleted it. I can't check the phone as he is out of the country. If it was to of gone onto the iphone is there a way i could remove it using my phone?

This is a simple task to achieve. The act of erasing all personal content and settings is called "factory resetting". Follow the following instructions:

1) Go to "Settings".

2) Next, tap "General"

3) At the bottom, you should find "Reset". Tap on it.

4) Finally, click on "Erase All Content and Settings".

There will be a warning that says something like "This will delete all personal media and settings. Proceed?" Just tap on Erase iPhone.

After that, your phone will probably load up and will act like a new iPhone right out of the box. Then you can give this to the new owner!