I like keeping it simple and straight to the point. These are some of the most common emmet codes to complete HTML tags. these emmet shortcuts will help you save time when you are coding. I have used these shortcuts in visual studio code and in sublime text editor. the [tab] means you just hit the tab key stroke to autocomplete the rest of the tag and in some examples after you hit the tab key, it will created the grandfather, father and children. so lets start using the ul tag because you can have children with this tag.
u + [tab]
<ul></ul>
u.class + [tab]
<u class="class"></u>
u#id + [tab]
<u id="id"></u>
u>li + [tab]
<u>
<li></li>
</u>
u>li*5 + [tab]
<u>
<li></li>
<li></li>
<li></li>
</u>
u>li*10>a + tab // adds 10 list items
u>li.item-$*10>a + tab // adds 10 list items with each class
u>li.item-$$*10>a + tab // adds 10 list items with each class leading zeros
u>li.item-$$$*10>a + tab // adds 10 list items with each class
This guy has a very helpful video on what I just covered:
https://youtu.be/U4lFXtLF5Cs?t=35
https://www.youtube.com/watch?v=U4lFXtLF5Cs&t=38&autoplay=1&list=PLpcSpRrAaOaqQMDlCzE_Y6IUUzaSfYocK&index=7