How to do so that fixed navigation bar doesn't cover content by clicking a button that drops to another part of the web.

Hi Patricia, I've done a quick CodePen that you can use for reference, but here's the main technique I've used:

section {
  position: relative;
}

section::before {
  display: block;
  content: '';
  height: 40px; /* Adjust to match the height of your fixed navigation */
  margin-top: -40px; /* Apply same adjustment as above, so 80px above is -80px here */
}

If you've not yet encountered pseudo elements in css (ie ::before and ::after), then don't worry too much about it yet, Treehouse does cover them in their CSS courses.

Instead of H2 tags I'm using the navigation to link to sections with the particular ids, but this will work for your H2s as well.

The ::before pseudo-class inserts an empty block at the top of your element, so instead of the link taking you to the top of your H2 element, it would take you to the top of the empty space you've just created. I've set the 'content' to an empty string, but bear in mind you could use this to insert some text, symbol or icon instead. The height needs to be at least matching the height of your fixed navigation bar otherwise it won't prevent the overlap. The negative margin-top is optional, but is nice to include as it removes excess space between your elements.

There are JavaScript methods you can use to calculate an offset instead, but hopefully this should help to give you a good starting point.