Hi HannahSue, you can limit the number of posts you want to show on your Blog page by going to Editor > Blog feed > Settings > Layout, and scrolling down until you see Post Loading.
Select the option "With page numbers," and then select how many posts you want to show per page. Your readers will only see the X amount of osts you've selected when clicking on the Blog page. To see more posts, they can click on the page numbers at the bottom of the blog feed.
I hope this clears up the issue for you, and if you need anything else, just let me know.
Thank you so much!
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