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

Yes

The word "celebrar" is semantically, grammatically, and orthographically identical in both Brazilian and Continental Portuguese. There are no differences in meaning or spelling. The only differences are phonetic:

• Pronunciation: In Brazilian Portuguese, the vowels tend to be more open and the rhythm is more "syllable-timed," making the word sound more melodic. In Continental Portuguese, unstressed vowels are often reduced or "swallowed," making the pronunciation much more clipped and "stress-timed."
• Usage: While the word itself is the same, the surrounding vocabulary and sentence structure (such as the placement of pronouns) often differ between the two regions.

Brazilian Portuguese Examples

1. Vamos celebrar o aniversário dele hoje à noite. (We are going to celebrate his birthday tonight.)
2. A equipe quer celebrar a vitória com um churrasco. (The team wants to celebrate the victory with a barbecue.)
3. O juiz vai celebrar o casamento amanhã. (The judge will solemnize the wedding tomorrow.)
4. Precisamos celebrar essa conquista importante. (We need to celebrate this important achievement.)
5. A comunidade se reuniu para celebrar a Páscoa. (The community gathered to celebrate Easter.)

Continental Portuguese Examples

1. Vamos celebrar o aniversário dele hoje à noite. (We are going to celebrate his birthday tonight.)
2. A equipa quer celebrar a vitória com um jantar. (The team wants to celebrate the victory with a dinner.)
3. O juiz vai celebrar o casamento amanhã. (The judge will solemnize the wedding tomorrow.)
4. Temos de celebrar esta conquista importante. (We have to celebrate this important achievement.)
5. A comunidade reuniu-se para celebrar a Páscoa. (The community gathered to celebrate Easter.)