Android Game development

Hi,I’m working on Android Game. I have a doubt , when to use OnTouch(),OnPressed() in UMG?
I tried using OnPressed() its working as expected in mobile ,then what’s the use of OnTouchStarted() and when to use it?
If we are making game for mobile do I need to use Input bindings as InputPlayerComponent->bind touch() or InputPlayerComponent->bind Action()?

How to host a server for manifest file(for chunks downloading)?

Thanks!