Canon EOS R50 Instruction Manual page 486

For RF lenses with a focus mode switch
Set the lens focus mode switch to <
2.
Magnify the image.
Pressing the <
magnification ratio, as follows.
3.
Move the magnified area.
Use the <
focusing.
To center the magnified area, press the <
> button and then the <
> keys to move the magnified area into position for
443
>.
> button changes the
> button.