I’m a huge proponent of Grid, but some people tell me they prefer the simple approach to layouts you can take with Flexbox over the more complex layouts of Grid.
To me, the issue arises from people kaing an overly complicated approach to using Grid, which is one of the reasons I’ve avoided talking much about defininig rows so far.
Here’s a layout that some people might make an overly complex Grid for that I found on Dribbble.
This is not to say that you can’t come in with more complicated approaches in some of these situations.
I can easily see how Subgrid could be beneficial for a layout like this, but more often than not, a very simple approach is best. It keeps the code small, easy to understand, and easy to maintain.
Additional Resources
This should be enough to get you going with Grid, but it is a much bigger topic. We haven’t talked about a lot of features that you have, but I you can do a lot with what we have covered.
If you’d like to learn more, Jen Kramer has Ultimate CSS Grid & Layout Techniques here on FrontEnd Masters.