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

Yes

The spelling, meaning, and grammatical function of "começa" are identical in both Brazilian and Continental Portuguese. The only difference is in pronunciation.

In Brazilian Portuguese, the vowels are generally more open and clearly articulated. The unstressed "e" in "começa" is pronounced clearly as a mid-front vowel.

In Continental Portuguese, unstressed vowels undergo significant reduction. The "e" in "começa" is often "swallowed" or becomes nearly silent, making the word sound much more clipped and consonant-heavy, with the emphasis shifting more sharply to the stressed syllable.

Brazilian Portuguese Examples

1. O filme começa agora. (The movie starts now.)
2. Começa a chovendo muito forte. (It is starting to rain very heavily.)
3. A aula começa às oito horas. (The class starts at eight o'clock.)
4. Tudo começa com um pequeno passo. (Everything starts with a small step.)
5. Ele começa a trabalhar amanhã. (He starts working tomorrow.)

European Portuguese Examples

1. O filme começa agora. (The movie starts now.)
2. Está a começar a chover muito forte. (It is starting to rain very heavily.)
3. A aula começa às oito horas. (The class starts at eight o'clock.)
4. Tudo começa com um pequeno passo. (Everything starts with a small step.)
5. Ele começa o trabalho amanhã. (He starts work tomorrow.)