This is genuinely a serious comment but have you read the Bible?

I don't really have one thing answer for you.
If you want to get a feel for what leftist Christians believe you could try lurking r/radicalchristianity there can be good discussion on there and you should get a feel for things, and people often drop book names you can read.
You could also read some articles by the Institute for Christian Socialism, which is linked in the sidebar, that may help.
Damon Garcia could have some good introductory/overview videos and there is also this video on Christian Anarchism that I think can do the same.

And of course you can always stick around here :3
We have a Book Club and Bible Study that are struggling to get off the ground.

You can also ask people here questions, but they might not always have an answer for you.

https://tribunemag.co.uk/2019/04/tony-benn-on-revolutionary-christianity