Hi Mo,
It's ages since I earned the B Villa , but, from memory I think the Villa was earned by doing flights to the Brazilian destinations and/or visiting certain buildings on your neighbour's airports. When you carry out these tasks, you occasionally get gift items drop that contribute to the quest, but this doesn't always happen so you need to be patient and keep trying until you reach your goal. Achieving quests such as these and constructing the resultant buildings is a big part of the game and new quests will open almost every time that you complete the previous one. Some quests are only available to higher level players, but all come sequentially in time as your game matures.
The only exception to this is when quests come along that are related to world holidays and special events. The next of these is expected to be a special Christmas event, ( it isn't out yet) but you may not be able to see this quest when it's launched or achieve it because of limitations in what you can do at your game level. For instance, bigger, aircraft with new longer timed destinations will only be available at certain levels and they are relatively costly to buy so you need to build up your stash of coins.
You will see many of the buildings that you are trying to earn on other, more advanced players' airports.
When you click on the quest icon in the top left corner of your game it should tell you exactly what you need to do to earn the particular building.
Just be aware that some things like the Brazilian Villa cannot simply be purchased directly from the store.
I hope that this helps. I'm sure that other people will advise further.
If my explanation isn't sufficiently clear, then please advise and I/we will try to offer further help.
I'll send you a friend request but you may not receive it because of technical limitations within the game. You can also try to add me.
Nuttyuk