bitcoin core – transaction of the lighting network

I've never used LN, but I read about this and I'm confused about one thing, if I'm sending BTC through the channel, then the receiver knows exactly who sends this and can somehow verify how much is left of the sender's balance and even find the original BTC address. that create the sender's channel? I only know that the transaction is sent in the form of an onion, so the participants do not know if the sender is the type that sends it by mail, or if the next recipient is the final recipient of the transaction.