As has been said that is the official site, totally legit.
I have been to the Baku F1 race a number of times now, the first being in 2019. A number of pointers i can give you, the first of which is to try to get a direct flight. If you have to book a flight with a stopover, don't stopover in Istanbul. The new terminal building there is over half an hour of taxiing on landing and take off, so a 4 hour stopover is actually 5 hours minimum.
Don't book a hotel in Baku, Air B&B is a much better option and cheaper. The food in Baku is so good and so cheap, there really is no point in paying for hotel food. Not only that, there are lots of B&B's to choose from that overlook the track, so in theory you don't even need to buy a grandstand/track ticket. I always have had a grandstand seat though, the best of which is behind turn 6 and facing turn 20. It's the grandstand that gets you the biggest view of the track and because the cars are flat out at the exit of turn 19 down to turn 1 it gives you the best sound, particularly the F2 cars.
Without any doubt in my mind, Baku is the best value for money F1 race there is at the moment. The place is great, the racing is always eventful, the people are very friendly, the food is second to none and the Air B&B's are some of the best around.
Just get the flights sorted properly and it becomes the perfect holiday for an F1 fan.
Edit: Something to be aware of, particularly for "girlfriends" in high heels. The pavements in Baku are very high above the road surface (some can be over 12 inches) and are not flat and level. It's not a good idea to walk around with high heels on.