I use the <p> tag to space out my paragraphs, but do I need to end it after each pargraph? It still gets the spacing right.

no, but if you have stuff other than those paragraphs under it you might want to end it.

Although you probably should anyways. Because it will help you get in the habit of using closing tags so when you come across a tag the does need a closing tag you will use it. :)

<p>
it is good programming practice to use closing tags.
</p>