First and foremost welcome to Scratch! Scratch is such an amazing and welcoming community to be in. But for me getting started was rough. Trying to get used to the Scratch editor and how to get a lot of views and follows. Even thought that is not the point of scratch I think we can all agree that it feels nice to be noticed for doing something we love. But to get to the point if you want a good starting point check out my studio The Ultimate Guide to Scratch. This is perfect for New and experienced scratchers! Every project is mobile friendly which means you can use them on a computer as well as a phone or tablet! Here is the link to my studio so you can get coding!
https://scratch.mit.edu/studios/51809723/

It's really nice that you want to help out with a guide! However, we have a number of them in the forums already and we don't have a good way to showcase any more. If you want to make a guide in a Scratch project, that would be fine. You could advertise it in the “Show and Tell” section too.

There are lots of other ways to help out in the forums too. Helpful Scratchers are always welcome in the “Questions About Scratch”, “Help With Scripts”, “Requests” and other sections. Just look around and ask questions