This page lets you generate a bunch of different fonts that use cool fancy symbols 𝓁𝒾𝓀𝑒 ⓣⓗⓘⓢ. The characters that you see on your your keyboard are only a tiny fraction of all the characters that are actually available. The Unicode standard has over one hundred thousand unique characters, and it's still growing! Using this web page you can convert normal text into a bunch of different fonts that use some of these 100k+ other symbols to create "pseudo-fonts" that you can use in your Instagram bio, usernames, chat messages, internet comments, and a million other places.
Wondering how all these different text fonts came into existence? Well, when Unicode was initially being formed, there were a bunch of big players in the computing industry who each had their own ways of encoding text as binary data, and they each had sets of characters that they relied upon. So to convince them to adopt the Unicode standard, the founders of Unicode needed to include all the weird characters from all of these companies. This let to an explosion of the number of characters, and even to many duplicate characters (characters that are actually different, but that look the same). On top of this, in the early days of computers, academics wanted to be able to use special symbols for their equations and stuff when they were communicating with one another, and so there were a bunch of "pseudo-alphabets" added for this purpose (like 𝕥𝕙𝕚𝕤 𝕠𝕟𝕖, and 𝐭𝐡𝐢𝐬 𝐨𝐧𝐞, for example). Over time, more and more characters were added, which made it possible to create many more different "fonts" out of them. For some "fonts" the symbols are even from other languages (like ㄒ卄丨丂 ㄖ几乇).
You should be able to just type your normal text into the first box and then copy and paste the font that you like. If you have any problems, let me know in the comments! If there are different fonts that you'd like me to include, then also let me know about those in the comments :)