Want to open a form from a link in a freely-selected place (not from the link within a list)

jcgonzalezmartin Sorry for the late response. Between having more or less development, the first answer would be, the less development, the better. But on the other hand, I really want to learn how to use, for example, the REST APIs SharePoint provides, so I can do further implementations myself when it becomes necessary. I just don't know how to start, how to implement development in the first place...

For this case, I am imagining doing something like this:

1. Create a form in html (the form will be a request form for documentation)

2. Use REST API to get the data input in the form when someone fills it and hits the send button (or something like that)  and to add these data to a specific list in my SP2013 site

3. Create a workflow to alert the related people when an new item is added to the list

I believe that step 1 consists just in creating an absolutely normal <form> in html. 

Also, step 3 using an absolutely normal alert workflow in SPD.

My problem is how to implement step 2. I found some code examples but sincerely, I just don't know how to work with them...

If you could give me any help with this, it would be really great!

Thank you very much in advance.