Sincere respect for putting yourself out there with your post and saying that you are finding the learning journey challenging, a lot of people might not do that, some might just give up, it’s great to see that you are keen to keep progressing.
As with anything new, the learning journey can be challenging and will always be unique to the individual, with often no one solution being perfect for everyone. The Unity Scripting API is a good example of that. Some of the content in it is very straightforward and explained well, other areas less so, and some, well, you only get a brief description. Being able to consume resources such as that, or perhaps Microsoft’s own documentation for classes, methods and so on takes time, but stick at it, because you will find it gets easy the more you do it.
On that very note I would wholeheartedly recommend looking at the Unity Scripting API not only when something doesn’t click with you, but also when it does, this will give you more experience with their documentation and the way it is written and will help over time, and hopefully make the experience easier when you’re looking up something that hasn’t yet clicked.
With regards to other resources, well, there’s going to be a whole internet full of them, but sending someone to the place that is just right for them would be quite challenging, instead, what I would offer as advice would be to reach out whenever something isn’t clear. Whether you post your questions on the Udemy Q&A to get a response from one of the student instructors, or perhaps on the Discord channel, or here, you will invariably always get a response from someone willing to help you out, and if the response you have had isn’t clear enough for you, just ask them nicely to explain it in a little more detail - it’s a great community with lots of people willing to share and help each other.
I hope the above is of some use to you, and again, sincere respect for raising your hand and saying “hey, I’m not getting some of this”, that takes courage and the questions that you may ask in the future will also help lots of other people who have perhaps had a similar experience but have yet to muster the courage to ask for help.