Hi Danny.
I can share with you some information about QuickBooks logins.
QuickBooks Self-Employed (QBSE) and QuickBooks Online (QBO) are two different subscriptions. Thus, linking their logins into one is currently unavailable.
To open your QBSE account, you can use this link: https://uk.selfemployed.intuit.com/home. And, here's for QBO: https://qbo.intuit.com/login.
If you have any other questions, please let me know by adding a comment below. I'm more than happy to help. Have a good one!