When we start with building Mandarin sentences, we usually need to talk about somebody or something. That’s why we’re starting right here with pronouns.
|我 - I
|你 - You
|他/她/它 - He, She It
Remember that all three third person singular pronouns are pronounced exactly the same way. They’re only differentiated in writing.
We can add the word 们 to mark a plural pronoun:
|我们 - we
|你们 - you (plural)
|他们 - they
You’ll also likely find 您 in introductory materials as a “formal” version of 你. It’s often used in formal situations in TV and movies, though many people prefer to just use 你 in daily life. Start out with 您 if you’re unsure, but don’t be surprised if you’re answered with 你.