how can I add 2 buttons at the bottom of the mobile menu?
To achieve that, you would have to add two more menu items, add a CSS class to them, and style them with a custom CSS code.
I can help you with that, but you must first add a class to them (you can name it however you want) and tell how they should look like.
Got it, many thanks!
Add menu item with Custom Links, and activate CSS classes field as shown on the screenshot from my previous message.