Help I can't change my ip address

[gw1]

I'm having trouble changing my ip address i have to change the first 2 sets of numbers and the 3rd number can be anything correct? Then i have to put in the subnet mask numbers that then the default gateway numbers that need to be typed in is that right.

The box for default gateway will not let me type anything in that box. Then you need put in the first DNS numbers i'm having a hard time with my ip address need help. Here are my numbers as they appear.

ip address number: 169.254.69.74
subnet mask number: 255.255.0.0
DNS number: 2001:558:feed::1 2001:558:feed::2
default gateway numbers: fe80:21d2ff:feb7:3831 %11
Need help

Thanks
gw1