I've been on Wattpad for a long time and I also write my own stories. I have seen with some authors how chapter headings are in a completely different font e.g. Courier New and not like the normal font I read in other ways. But somehow I can't do it with myself. I write using my mobile phone (Huawei Y6 2018) and my laptop in the browser.
Can anyone explain to me how it works?
There are some websites where you enter text and it then appears in a variety of forms / fonts. You then simply copy this text and then insert it again at the desired location. I haven't used these sites in a long time and I can't give you a specific website right now. Otherwise you can find a lot of sites online! There you can just try a few things.
I have nothing to add to that, except one of the links mentioned.
https://lingojam.com/FontsForInstagram