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

Yes

The word "convidar" is identical in meaning, spelling, and grammatical function in both Brazilian and European Portuguese. The only differences are in pronunciation. In Brazilian Portuguese, the unstressed vowels are generally more open and clearly articulated. In Continental Portuguese, unstressed vowels (such as the "o" in the first syllable) are often more reduced, swallowed, or nasalized, and the overall rhythm of the word is more stress-timed.

Brazilian Portuguese Examples

1. Eu vou convidar meus amigos para o churrasco. (I am going to invite my friends to the BBQ.)
2. Ela me convidou para sair hoje à noite. (She invited me to go out tonight.)
3. Você vai convidar a sua irmã? (Are you going to invite your sister?)
4. Nós convidamos todo mundo para a festa. (We invited everyone to the party.)
5. Eles me convidaram para o aniversário. (They invited me to the birthday party.)

European Portuguese Examples

1. Eu vou convidar os meus amigos para o churrasco. (I am going to invite my friends to the BBQ.)
2. Ela convidou-me para sair hoje à noite. (She invited me to go out tonight.)
3. Vais convidar a tua irmã? (Are you going to invite your sister?)
4. Nós convidámos toda a gente para a festa. (We invited everyone to the party.)
5. Eles convidaram-nos para o aniversário. (They invited us to the birthday party.)