So... I have to learn reactJS for work. (Their entire frontend is built upon it) but I am really struggling through my first week. I feel like I don't understand it at all. Unlike angular where I feel like I picked it up pretty quick. Any ideas?

You need to approach it from a clean perspective. No redux, or any state management. It's a library for building UI, not a framework. You'll find that everything you want to build works in exactly the same way. There's practically no API to learn, apart from some stuff like componentDidMount and similar life cycle methods, and use props and state. It will all just fall into place and when it does, you can build anything. Then, when you recognise some common patterns, look at state management libs like redux or mobx.

It's pretty much the code itself. I just don't understand it when just looking at it. I find it very confusing, but I'm already included in three projects all which are built on react so I don't feel like I'm getting the time to learn, well, react.