On the last section of the application page here, you'll see the button to +Connect your Bank Account.
Simply click Connect to chose your banking institution:
Then follow the steps to sign into your bank and authenticate your login (TIP: please keep your bank login and password handy in order to complete this step):
And you'll see the confirmation on the last page that you've successfully connected your bank account:
Once approved - you can managed your Linked Accounts here in your Sorbet Account: