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

Yes

The word "juntos" is identical in meaning, grammar, and spelling in both Brazilian and Continental Portuguese. The only difference is in pronunciation. In Brazilian Portuguese, the final "s" is typically pronounced as a sibilant [s], similar to the "s" in the English word "sun." In Continental Portuguese, the final "s" is typically pronounced as a postalveolar fricative [ʃ], similar to the "sh" in the English word "shoe."

Brazilian Portuguese Examples

1. Nós vamos juntos de ônibus. (We are going together by bus.)
2. Eles estão sempre juntos no shopping. (They are always together at the mall.)
3. Vamos fazer o trabalho juntos. (Let's do the work together.)
4. Os garotos cresceram juntos. (The boys grew up together.)
5. Queremos viajar juntos nas férias. (We want to travel together on vacation.)

Portuguese (Continental) Examples

1. Nós vamos juntos de autocarro. (We are going together by bus.)
2. Eles estão sempre juntos no centro comercial. (They are always together at the shopping center.)
3. Vamos fazer o trabalho juntos. (Let's do the work together.)
4. Os miúdos cresceram juntos. (The kids grew up together.)
5. Queremos viajar juntos nas férias. (We want to travel together on vacation.)