Jacob Gube explains to beginners the basics of photoshop. He goes into further depth over the layers, filters, toolbox, and more. There are multiple tutorials within every topic. This site is like the google for photoshop dedicated to beginners. Whenever you have questions over the basic controls/uses for photoshop this site more than likely has the answer.

https://mashable.com/2010/08/12/12-beginner-tutorials-for-getting-started-with-photoshop/#8E55WicRRmql