So green wallet is a mutli signature type of wallet hence why it starts with a 3. Blockstream has a key in case you fuck up and lose funds. This is because of liquid and the way it functions. Its just how green works. Its a 2of2 multisig wallet. They only have a key in case you lose your device they could restore it for you.
Discussion
Ye I'm after my generic blockchain address for inputting my transactions but it won't accept the 3 address
What do you mean inputting your transactions?
Koinly tax
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.