Create WHMCS Add on for Local Bank Auto payment Confirmation

Hello, I Want to Create WHMCS Add on for Local Bank Auto payment Confirmation. With this add on, client can confirm their order from front end menu, then if the invoice number & the transffered money is correct this add on will activate the client order. To Check the confirmation, the add on need to login to registered internet banking account then check the transffered money & note of transfer. You can check my attachment for this add on workflow.