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

Yes

The word "lagos" (the plural of lago, meaning "lakes") is identical in both Brazilian and Continental Portuguese in terms of spelling, meaning, and grammar. The only difference is pronunciation. In Brazilian Portuguese, the unstressed "o" is typically pronounced as a more open or semi-closed /u/ sound. In Continental Portuguese, unstressed vowels are much more reduced or "closed," often resulting in the "o" sounding like a very short, muffled /u/ and the "s" at the end of the word being pronounced as a "sh" sound (/ˈla.ɡuʃ/).

Brazilian Portuguese

1. Existem muitos lagos lindos no Canadá. (There are many beautiful lakes in Canada.)
2. Nós vamos visitar os lagos da região. (We are going to visit the lakes in the region.) /3. Eu gosto de nadar nos lagos. (I like to swim in the lakes.)
3. Esses lagos estão muito limpos. (Those lakes are very clean.)
4. Os lagos congelam durante o inverno. (The lakes freeze during the winter.)

Continental Portuguese

1. Existem muitos lagos lindíssimos no Canadá. (There are many very beautiful lakes in Canada.)
2. Nós vamos visitar os lagos da região. (We are going to visit the lakes in the region.)
3. Eu gosto de andar a nadar nos lagos. (I like to go swimming in the lakes.)
4. Estes lagos estão muito limpos. (These lakes are very clean.)
5. Os lagos congelam durante o inverno. (The lakes freeze during the winter.)