All good advice. The OP was asking how to get back to a forum section list, instead of a particular or subscribed post.
Using the same pic, you will notice that the circled text is actually hyperlinks.
Clicking the blue circled one will take you to the main forum list (or home page).
Clicking the yellow one will take you to a particular subforum list of the main one.
Clicking the red one will take you to a list of all threads in a particular subforum
If you want to use your windows keyboard (not sure on a Mac) instead of a mouse, you can actually do it even quicker and don't have to click on the forum list or even the back button. I know this works in Firefox but others will need to try other browsers to see.
Just hold down the "Alt" button and hit your left arrow key. It will take you back one page/list..... depending on which list you came from.
If you were on the main forum page and clicked on a recent post title, then you went directly from the main list to the post...so using the alt-left arrow key in that case would take you back to main forum page.
However if you went from the main forum page, to a subforum list, then a thread list, then a post......... then using the alt-left arrow key would take you back in reverse one page at a time.
I use both methods depending on which computer I may be at, and how I am sitting in relation to a keyboard.
EDIT: I just tested the keyboard shortcut in Microsoft Edge and it works the same as Firefox.