You can book your flights either online at ba.com, by phone with a British Airways service centre, or through your travel agent.
Whichever you choose, you will earn On Business Points as long as your company’s On Business membership number is in the booking of every qualifying flight.

To earn points when you book online, be sure to enter your On Business membership number. Or quote it over the phone if you are booking with a British Airways service centre.

Give your nominated travel agent your company’s On Business membership number and ask them to use it whenever they book your flights.

Flights booked using a GDS system must have the
On Business membership number entered using the appropriate code.

It is entirely up to you how you choose to spend your points. You can redeem them on flights, upgrades or Marriott hotel e-certificates.