Since the Articles Field Custom HTML Layout pertains to each individual article, it's a bit tricky if you wanted to display the linked articles in a bulleted or numbered list.

But it can be done. Starting from Joomla 4, you can assign a Prefix and Suffix to custom field values, which makes it therefore possible to add any code around the output of the whole custom field.

So, under the "Options > Render Options" of your custom field, you can give a Prefix of <ul>, and a Suffix of </ul>.

Now, in the Articles Field Custom HTML Layout, you can simply surround the article output with <li></li> tags.

<li><a href="[url]">[title]</a></li>