How do I create summaries of posts on my home page?

I guess what you’re asking here is how to just post, say, the first paragraph of a post on the front page?

If so, you can use the ‘Insert More Tag (Alt-Shift-T)’ in the post editor when you create or edit a post. It’s between the ‘Unlink’ button and the ‘Spell Checker’ button.

When you insert a ‘more’ tag, everything prior to it in the post is displayed on the list, but the whole post is displayed in the single post output.

I hope I understood correctly what you were after.

HTH

PAE