To Help, To Assist, To Lend A Hand
transitive verb, godan verb
When you transmit your hand to something or someone, you're putting out your hand to help them or to assist them.
てつだう
Both of these are the kun'yomi readings that you've already learned! The thing is, the た from 伝's つた changes into だ for who knows what reason. Perhaps you can ask for someone to help you to understand this dumb reading change.
あ、手伝うよ。
Oh, I'll help.
ごめん、ちょっと手伝ってくれない？
Sorry, could you help me out a bit?
手伝ってあげたいのはやまやまなんだけど、私にはどうにもできないんです。
I really want to help, but there's nothing I can do.