Is the word vão the same in Brazilian and European Portuguese?

No.

While the dictionary definitions, spelling, and core meanings of "vão" are identical in both dialects, there is a difference in typical usage. In Brazilian Portuguese, "vão" (the third-person plural of the verb ir) is the standard and most frequent way to express the future in spoken language, almost always used as an auxiliary verb followed by an infinitive (e.g., vão fazer). In Continental Portuguese, while "vão" is used, there is a much higher prevalence of the synthetic future (e.g., irão) or the use of the simple present tense to indicate a future intention.

Brazilian Portuguese examples:

1. Eles vão chegar tarde. (They are going to arrive late.)
2. Vocês vão fazer o quê? (What are you going to do?)
3. Eles vão me ligar. (They are going to call me.)
4. As crianças vão brincar agora. (The children are going to play now.)
5. Eles vão comprar um carro novo. (They are going to buy a new car.)

Continental Portuguese examples:

1. Eles chegarão tarde. (They will arrive late.)
2. O que é que irão fazer? (What will you do?)
3. Eles ligar-me-ão. (They will call me.)
4. As crianças brincarão agora. (The children will play now.)
5. Eles comprarão um carro novo. (They will buy a new car.)