You will be learning how to read chord boxes in the initial stage since it forms the basis of guitar playing. As for tabs, you may not need to learn them yet. However, I will give you a brief lesson on them here for you to correctly understand the basics. I strongly discourage beginners from reading music notations since it results in slow progress.
Reading Chord Boxes

As a beginner, there are three easy chords you must know about: Chords A, D, and E. The chords are very basic strumming. We will add other chords to broaden your knowledge. Besides, there are easy songs you can play using these three chords. While sitting and trying to play may result in sore fingers, I assure you it will be lots of fun!
The D-Chord