To go back to using a regular password:
Go to the access management page.
Switch off Two-factor authentication.
On the page that opens, enter a one-time password from Yandex.Key to confirm that you are disabling 2FA.
If the password is entered correctly, you will be able to set a new regular password for your account.
You will need to create new app passwords for third-party apps and mail importers because your old passwords will stop working after you disable 2FA. New passwords can be created on the access management page.