I am building a React.js blog site with create-react-app for someone else and I want them to be able to type their blogs in Google docs, Google forms, or any other website and have it automatically update on the blog site. I've tried using services such as Zapier to connect these third party softwares to Firestore but it becomes difficult when the blog post includes special text formatting such as images, bold/italics, etc. I'm not sure how I would convert this to JSX from a third party website.
I've also looked at services such as Gatsby or Butter CMS, but most of these are either not free or require me to re-create the website entirely with a different CLI. I need something that's free for at least 75 blog posts a month.
Ideally, I would be able to allow my client to type their blog posts in a Google doc or any other document/website, and I would be able to take that content and directly post it on the blog site. Again, this includes images within the blog post, special text formatting, etc.