
li#menu-item-14341 > a::before{
content: "\f0e0";
font-family: "Font Awesome 5 Pro";
font-weight: 600;
line-height: 1;
margin-right: 10px;
}
The only requirement would be to know the ID of your menu item. If you know CSS, you can improve it a lot more to be able to reuse the code in several elements at the same time. I have only given you a quick and practical example.
Kind regards.