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

Yes

The word "portas" is identical in meaning, spelling, and grammar in both Brazilian and Continental Portuguese. The only difference lies in pronunciation.

In Brazilian Portuguese, the vowels tend to be more open and clearly articulated. The "a" at the end of "portas" is pronounced clearly. In Continental Portuguese, unstressed vowels (like the final "a") are often "reduced" or even suppressed, making the word sound more closed or shorter to a Brazilian ear.

Brazilian Portuguese Examples

1. As portas do ônibus estão abertas. (The bus doors are open.)
2. Feche as portas antes de sair de casa. (Close the doors before leaving the house.)
3. As portas do shopping fecham às dez da noite. (The mall doors close at ten at night.)
4. Ele bateu nas portas do quarto. (He knocked on the bedroom doors.)
5. Precisamos de portas novas para a reforma. (We need new doors for the renovation.)

Continental Portuguese Examples

1. As portas do autocarro estão abertas. (The bus doors are open.)
2. Fecha as portas antes de saíres de casa. (Close the doors before you leave the house.)
3. As portas do centro comercial fecham às dez da noite. (The mall doors close at ten at night.)
4. Ele bateu às portas do quarto. (He knocked on the bedroom doors.)
5. Precisamos de portas novas para a obra. (We need new doors for the renovation/construction.)