How do I create a website that combines user input and standard text and converts it into a pdf?

Question

There's this annoying form that we have to fill in at work for every case in a word document. FIlling it in consists mostly of choosing what standard text applies, and removing the text that doesn't apply. It takes a lot of work because you have to delete the text that you don't use, and format it properly.

I want to create a website that generates the final text based on the decisions that the user makes. The user can choose/click the text that applies, and the rest of the text is automatically deleted. Here and there they can add their own text.

At the end, I want the website to convert the final text into a PDF.

In short, the website starts with a rough outline of the document and returns a final result based on client input and decisions that they make.

How would I tackle a project like this? What steps are required to complete the project?

I have thought about it myself, I think it should be something like this:

1. Create the html

2. Create the js that allows to remove text based on user input

3. Ensure proper formatting

4. Convert the website/html into pdf??

5. (optional) add some css

How does step 4 even work? And is step 3 straightforward? As in, when you convert a html website into a pdf, does it normally keep the formatting that you see or do I need to keep other things in mind.

I feel the least confident in step 4.

The best thing I've made up until now is a calculator, based on the final Odin project of the fundamental course.