I
Me
noun, の adjective
The kanji and the word are exactly the same. That means they share meanings as well.
Keep in mind that 俺 has a more informal and masculine sound than neutral options like 私 and 僕. While it carries a rougher vibe, it's not solely reserved for tough personalities and is very common in casual chats among buddies.
The reading is the same as the one you learned with the kanji.
俺は生ビールにするよ。
I'll have a draft beer.
こいつ、俺のツレなんだ。
He's my buddy.
あ、いいよ、俺がやるから。
Oh, that's okay, I'll do it.
やあ、コウイチ！俺、久しぶりにお前に会ったから、話したいことが山ほどあるよ。
Hey Koichi, we’ve got a lot to catch up on.