The cPanel login details along with Quick Start Guide are sent to you in the email with the Hosting Guide for yourdomain.tld subject. It is sent to the email address assigned to your hosting billing profile, so please check your Inbox as well Spam/Junk folders.
Also, here are cPanel login links, listed in the order of preferability. You may use any, but we recommend the first three:
NOTE: yourdomain.tld is to be substituted with your actual domain name. If you choose the link with "serverhostname" or "serverIP", use the corresponding value indicated in your Hosting Guide.