To add your own blocks to the home page is quite simple.
First you’ll need to go to Posts -> Categories and then create a new category for your home page blocks.
Then once you’ve created that category, if you go into the category you’ll be able to get the category ID from the url bar.
This category ID ( called “tag_ID” in the url bar ) is what you’re going to enter into your “Home Categories” setting.
Then navigate to Appearance -> Customize and go to “Home Layout Options” and enter the category ID into the “Home Categories” section.
Then your home page should only show all the posts tagged into this category.
Make sure you tag the posts you want on the home page into this category.
If you do not create the home blocks category and tag selected posts to show on the home page then the theme will display ALL posts on the home page, and this can affect loading time is you have too many posts loading at one time.