Can I build the markdown previewer without React?

I am using the Front End Libraries Projects - Build a Markdown Previewer(https://www.freecodecamp.org/learn/front-end-libraries/front-end-libraries-projects/build-a-markdown-previewer) project as an outline for completing for a similar project.
I am wanting to build this with only vanillaJS if possible, I have not found any resources on this though and I am pretty confused on where to begin. I am still planning on using the marked library resource provided in the project unless there is a better suggestion. Also with this library I haven’t been able to get it to work, or more implement it in the project.
So my main question is, is it possible to build this only using vanillaJS and if so, any help/resources would be greatly appreciated!

Of course you can use vanillaJS to create the markdown-previewer but I think it defeats the purpose of learning react and redux. So, I suggest you to do it with react. If you need any help, you can always post your query here in the forum.