https://www.luckypatchers.com/how-to-use/

Some apk can mod without root. But there can't mod server side games (its not possible even if you have root permissions.). If you mod & installed it there is lot of disadvantages.

Can't login play service to that mod app.

Can't sync your apk data with there servers (mean if you Uninstall app, you loose your progress)

Dosen't show up Google updates for that app. (each update you must manually download & mod & just install. Don't uninstall current mod app). 

Some app can crash if there are protection on that app. 

If you want to root your device use kingroot. But your device warranty or any other services provided by device creator's will be void.