Fill and Loading

I know this is not a place for asking about other apps but please i need to know these so please don’t flame me(i will be using it for blender anyways)…

I am a newbie to photoshop so bear with me. Can someone tell me how to fill a layer with a pattern and how load a pattern as a selection in photoshop.

I would be most greatful if someone could answer this. Thanx

Nims