Hello Tinboye !
Seems your main current problem is in this part:
"Once you are now at 9.0.1, you will need to edit the inc/classes/BxDolUpgrader.php again and add /beta/ to the URL like this:
protected $_sUrlVersionCheck = 'https://v.una.io/beta/';
Go back into your Dashboard and check to see if you now see a 10.0.0-B1 is available. If you do not see it, clear your cache and refresh the page.
If you see the option, Click to upgrade to 10.0.0-B1. Your modules will again try to update and this time, it should be successful. " (c) Chris