RDII 20w type c fast charger on Iphone XS MAX

when im charging my xs max using 20w it gets the job done. But it gets more hotter than the usual slow charging method.

Is it ok to use the said fast charger on my XS MAX? Im a newbie in ios ang i want to clear my mind from overthinking.

i also need advice about how my battery’s health will become safe from dropping.