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

Yes.

The word abrem is the third-person plural present indicative of the verb abrir (to open). The spelling, grammatical function, and meaning are identical in both Brazilian and Continental Portuguese. The only difference is pronunciation: in Brazil, the unstressed vowels tend to be more open and clearly articulated, whereas in Portugal, unstressed vowels are often highly reduced or nearly silent, making the "e" in "abrem" sound much more clipped or swallowed.

Brazilian Portuguese examples:

1. Eles abrem a loja muito cedo. (They open the store very early.)
2. Eles abrem as portas do ônibus. (They open the bus doors.)
3. Eles abrem a porta do trem. (They open the train door.)
4. Eles abrem o celular. (They open the cell phone.)
5. Eles abrem a bala. (They open the candy.)

Portuguese (Portugal) examples:

1. Eles abrem a loja muito cedo. (They open the store very early.)
2. Eles abrem as portas do autocarro. (They open the bus doors.)
3. Eles abrem a porta do comboio. (They open the train door.)
4. Eles abrem o telemóvel. (They open the cell phone.)
5. Eles abrem o rebuçado. (They open the candy.)