Error: Could not find a canister id to forward to

@enzo After following your instruction every time I’m getting below the error.
open http://localhost:8080/?canisterId=rrkah-fqaaa-aaaaa-aaaaq-cai

Warning: unknown mime-type for "http://localhost:8080/?canisterId=rrkah-fqaaa-aaaaa-aaaaq-cai" -- using "application/octet-stream"
Error: no such file "http://localhost:8080/?canisterId=rrkah-fqaaa-aaaaa-aaaaq-cai"

But if I do the dfx start dfx deploy npm start not getting any error but browser asking me username and password. I tried ubuntu username password but it did not worked.

Please check stack over flow link for my detailed issue with screen shot : - Stack_Question
Please answer my question to get me started.
I also referred to given link :- from @kpeacock