Go to this link to know about adding blocks in your theme
How to add Blocks in your theme using Gutenify? #
Gutenify Plugin allows you to add our blocks in your page or post. Here are the steps how you add it:
Step 1: Install and activate plugin
Step 2: Click on the Page or Post the place where you want to add Gutenify Blocks
Step 3: In Page/Post click on “+” sign, there you will find default blocks option along with Gutenify’s options. Gutenify’s option is highlighted by Blue color
Step4: Click on the blocks you want to add in your Page/Post, Click on “Browse All” to see all the blocks and scroll all the way down
Step 5: Select the block you want to add and edit accordingly
Step 6: Finally, click publish to save