Thats a very "special" keyboard you bought. My best suggestion is to buy something proper.

But you could try something like Autohotkey to rebind keys (not sure if it works with ESO, never tested), also be caution because it might be detected as cheating, especially if you do more than a simple remap with it.

Another way is to remap keys via registry (be caution here too, especially if you arent experienced with such stuff!):
https://isenselabs.com/posts/keyboard-key-kills-and-remaps-for-windows-users

This way I remapped Caps Lock (one of the most annoying and useless keys that a keyboard can have!) with backspace, which can be used in almost any game, for example in ESO for dodge rolling. Once I used this to remap Caps Lock to F13, but about 50% of the games dont recognize the F13 key.