Oh you're gunna need this

You want an Xpub to import all your addresses that you've used.

Scroll to the end to see how to do so. I've never done this tho. So I'm not sure entering your private key somewhere is safe. But the Xpub is what you want for koinly.

https://support.koinly.io/hc/en-us/articles/9916030023452-How-to-get-the-xpub-from-different-wallets-BRD-Ledger-Jaxx-etc

Yeah if you only have a few txs then add them one at a time to koinly.