Is it possible to enable underline keyboard shortcuts and access keys?
Solution 1:
macOS does have keyboard shortcuts, but they do not display with underlined letters. Many menu items will display their shortcut to the right. Some menu items will not have a shortcut.
If the menu item doesn't have a shortcut, you can press Command + Shift + / to open a search bar that will let you type in the command. You can arrow down and hit return to activate that menubar item.
You can also arrow through the menu bar by pressing Control + F2 (or Control + Fn + F2). You may need to toggle this on with Control + F1.