First up, hi, welcome, etc. Second, things and questions like this should go in the writing workshop, and they have been answered in there a few times.
Create a variable, PLAYERNAME
Page with a list of names (don't both using a userinput one, to make it with anything more then 2 or 3 letters, is monstrously annoying. You'd need to have a page with 26 links for each letter, repeat for every letter. Not difficult, just tedious). ANyway, link 1 = Ted, set Playername to 1. Link 2 = Ajax, set playername to 2. In the places you want to use their name in text, just need to call it back (If PLAYERNAME = 1, "Ted", if Playername = 2, "Ajax", etc)