I forgot icloud login and password

You will have to try to recover the password or contact Apple for help.

https://iforgot.apple.com/

IF you still cannot recover it, contact Apple according to the instructions here.

Apple ID: Contacting Apple for help with Apple ID account security - Apple Support

Welcome to the Apple community.

Unfortunately, unless you know the Apple ID, there is absolutely nothing that can be done, you cannot use your mobile device. You may be able to find your Apple ID at Look up your old and forgotten Apple ID