I'm using Asus RT-AC68U. Asus routers are quite solid, but price is slightly on the high side.

If you're on a budget, TP-Link Archer C20 is a good option. (RM150~RM200)

You'll need your Unifi password with you when u set up the router. It's written in your service invoice. If you've lost it, then you can call Unifi to check.

the password you've changed is just wifi password. Unifi password is given by Telekom, is unique and unchangeable from normal user.
To watch HyppTV, you'll need all 3 of the boxes.

If you're only using the internet, you can switch off the HyppTV box.