Congratulations, is a way of showing someone your positive regards, appreciation, and kind words in order to make them feel accomplished in what they have done. Being able to congratulate someone at the right time, using the right words, in the right manner can be a stepping stone for some.
However, when you are trying to learn English this may be a somewhat difficult thing to do. But this is not something you cannot learn. Communicating the right words become so much of an easier task when you have a good grip and a good command over the language you are using.
When talking about congratulating teams one needs to understand that a whole collective group is what they are talking about, not just one individual but a team. The phrases or words you select to use must have the capacity to convey the message which you try to communicate.
The reasons can be various for congratulating a whole team, they might have won a match, gave outstanding performance, or simply because you value their efforts and you are honestly proud of what they have achieved. No matter what reason you have for congratulating a team, your choice of words is what delivers your thoughts, be sure that you choose the right words for the situation.
In order to be able to congratulate a team, for something, you also need to understand the complexity of their actions and may be use that to congratulate them suppose “I saw how hard of a competition you have, it is remarkable” what you did here is you figured out one thing they did on the field and congratulate them with it making it a compliment. This also shows that you are not happy for their performance but you put in time and concentration to see what was going on there.