That looks like a micro deposit eBay have sent to your account for you to confirm back to eBay , so they know they have the correct bank account to send your payouts, when you withdraw your money.
Look through your eBay messages , or is there a banner across the top of your main overview page saying 'Update your Account'. Click on that, to enter that micro deposit.
@fargvs has given you excellent links to read about registering for selling, registering for eBay's Managed Payments.
@panspitstop
