H1 means heading level 1

P tags define paragraphs of text. Most extra spaces are ignored, including line breaks,

inside of
some tags.

There are other very useful tags

For historic reasons, links are called anchors. Anchors are created with the <a> tag combined with an href attribute. This tag is very important, of course, to link to other pages.

The full name for a link is a hyperlink. The H in HTML stands for HyperText: HyperText is text with hyperlinks. Now you know ;)