Hello everyone, new member here. Let me recommend a site where I learned basics of PS, for free

http://wegraphics.net/tag/photoshop-beginners/

Basically, once you're done with all of the six exercises, you will be able to follow any tutorial whatsoever. You start of course, with the pen tool, the oldest entry, and proceed going through the layer masks, which are really basics of the basics.

Cheers.