The platform automates most of the hosting and management of your sites for you. You don’t need to worry about things like security, backups, updates or performance.
Once DNS is resolved, you will be able to log in directly from the platform without the need for credentials on the websites page.
Or you can log in from the 'Manage Website' (gear icon) section:
Each website is set up with an Admin username the is randomly chosen.
Do not change the password of this user as it will affect the usage of the platform to edit the site.
If you want to give someone else access to log in directly to the site, create a new user in WordPress and direct them to the /admin or /login.php pages of the site to log in.