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

Yes

The word "notas" is identical in meaning, grammar, and spelling in both Brazilian and Continental Portuguese. It can refer to school grades, paper currency (banknotes), musical notes, or written memos. The only significant difference is pronunciation. In Brazilian Portuguese, vowels are typically more open and clearly articulated. In Continental Portuguese, unstressed vowels (such as the "a" in "notas") are often "reduced" or "closed," meaning they are pronounced much more briefly, sometimes sounding almost swallowed in natural, rapid speech.

Brazilian Portuguese Examples

1. Eu tirei notas muito boas na prova. (I got very good grades on the test.)
2. Ele tem várias notas de cinquenta reais. (He has several fifty-real bills.)
3. As notas musicais são difíceis de ler. (The musical notes are difficult to read.)
4. Deixei algumas notas no seu caderno. (I left some notes in your notebook.)
5. Você conferiu as notas fiscais? (Did you check the invoices?)

Continental Portuguese Examples

1. Eu tirei boas notas no exame. (I got good grades on the exam.)
2. Tenho duas notas de vinte euros. (I have two twenty-euro bills.)
3. As notas musicais são difíceis de ler. (The musical notes are difficult to read.)
4. Deixei algumas notas no teu caderno. (I left some notes in your notebook.)
5. Já verificaste as faturas? (Have you checked the invoices?)