What are some foundational texts for socialism, communism, and anarchism?

I'm a very left wing person and have very lightly dabbled in political philosophy in the past (I've read some Lenin, Marx, Engles, etc) but I struggled to understand alot of the works. I grasped the basic principles of it, but nothing more than an outline.

Due to the times we find ourselves in I believe it's more important now than at many other times to be politically literate. With all this in mind, what are some foundational texts I should start with to become more well-versed in my aforementioned ideologies? Alongside this, are there any good books covering the historical development and progression of these ideas? Thank you (: