I let my son use my phone, now the screen when opened is changed. What do I do to go back to factory settings?

A

AC Question

i let son use my phone, now the screen when opened is changed. What do I do to go back to factory se

Son borrowed phone opened to make a call everything was changed,from color, total layout changed on how to access anything is different from the original screen it came with. How do I find, then go back to factory settings.