I can not get authenticate iCloud sign in on PC app.

Hello 1OLDGUY1960,

Thanks for choosing the Apple Support Communities. We see you are trying to get an authentication code using two-factor authentication. We have a few steps that can help.

Get a verification code and sign in with two-factor authentication - Apple Support

Try following those steps. If you are still unable to get a code, please follow the steps below.

"If you can’t sign in, reset your password, or receive verification codes, you can request account recovery to regain access to your account. Account recovery might take a few days or longer, depending on the specific account information you can provide to verify your identity."

We hope this helps.

Cheers!