How can I find out the wallet address that sent btc to a trezor?

Long story short, like an idiot, I purchased BTC through Coinbase while I was still figuring out what it was. I bought a bunch, moved it to my trezor, and then deleted my Coinbase account as I was going to let it sit. Yes I'm also here in the future to agree that this was remarkably stupid to do. I have a "new" coinbase account, that I have since moved BTC to, and sold. How can I go about finding my cost basis from my original Coinbase account? Or can I?

PS I can find the transactions, but I don't understand what the "input" and "output" are. There's a "witness" that looks like a wallet ID but I have no clue what it is nor if it was mine.