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

No.

While the fundamental meaning of the verb remains "to need" or "to require" in both variants, there are significant differences in typical usage and grammar.

In Brazilian Portuguese, particularly in informal speech, the preposition "de" is frequently omitted after the verb (e.g., "Eu preciso ajuda" instead of "Eu preciso de ajuda"). In Continental Portuguese, the use of the preposition "de" is much more strictly observed and almost never omitted. Additionally, there are differences in subject pronouns (the use of "você" in Brazil versus "tu" in Portugal) and common vocabulary (such as "prova" in Brazil versus "exame" in Portugal).

Brazilian Portuguese Examples

1. Eu preciso de ajuda aqui. (I need help here.)
2. Você precisa fazer o trabalho. (You need to do the work.)
3. A gente precisa comprar pão. (We need to buy bread.)
4. Eu não preciso de nada. (I don't need anything.)
5. Você precisa estudar para a prova. (You need to study for the test.)

Portuguese (Portugal) Examples

1. Eu preciso de ajuda aqui. (I need help here.)
2. Tu precisas de fazer o trabalho. (You need to do the work.)
3. Nós precisamos de comprar pão. (We need to buy bread.)
4. Eu não preciso de coisa nenhuma. (I don't need anything at all.)
5. Tu precisas de estudar para o exame. (You need to study for the exam.)