magnification

What do you mean by magnification? You can go to Settings/Display & Brightness and change View to Zoomed. This will enlarge the icons on the Home screen.

You can also use the camera as a magnifier using an icon on the Control Center. If you don’t see it go to Settings/Control Center/Customize Controls, and you can add it.

If you want to enlarge the whole screen go to Settings/Accessibility/Zoom and turn it on. Note that you should read the instructions carefully on that page on how to use it.

If you mean something else please explain what you are looking for.

The Magnifier is in Settings>Accessibility>Magnifier. It is in the Vision Section.