来ます = 来
帰ります = 回来/回家
戻ります = 回来
Kaeru vs modoru is the more confusing distinction: Kaeru is used for 'returning home'
You see "modoru" in games where you press "return" to return back to a previous menu or screen. You would use "modoru" over "kaeru" to return to work or school
The phrase "Okaerinasai" is used when you see your family members returning home; a bit like when shop assistants say "irasshai(mase)"
Also when you're in someone else's house and they want you to go away, they may use "kaeru" instead of "modoru", sort of saying "go home please".
You probably also recognise 帰国 (return back to home country) which uses the onyomi form of the kanji for "kaeru"