In most of themes this section is by default available but if it's not available in the theme you are using.
You can follow this article to achieve it.
Thank you for your speedy reply.
I know this is a dumb question but if this is our blog: https://fawninteriors.co/blogs/journal what bits do I have to change in the code? Because I can't add a section in my Theme editor, so I need to add in my index.liquid.
There is no concern of this Blog template with section code. You have to just follow the article to add blog post in homepage.
And this code will no go in index.liquid