Welcome to Flyertalk and welcome to the BA forum. There is a guide to earning tier points and avios in the Forum Dashboard which you may find easier - those videos are hilarious for all the mistakes in them.

The big question is do you have a BAEC account already? If so does it have a year end date on it?

If not, your big decision is whether to get Silver before 31 March 2025 or after it. If you get it before, then you keep it from the point of hitting 600 TPs until 31 March 2026, so at least a year. On 1 April your TP collection gets zapped and you have to start again, but any status achieved before 1 April will carry over. Moreover if you do get Silver before 31 March 2025, not only does it last until 1 April 2026 but you soft land to Bronze from 1 April 2026 onwards - that at least gives you 7 day free seat selection and slightly better access through LHR.

As mentioned you need 4 BA flights, and / or 4 BA marketed flights, as well as 600 TPs, to get Silver. So if that Qatar flight is sold as a BA codeshare then that sorts as out that, but if sold by Qatar alone then it does not do so (broadly speaking).