As a beginner you can use expressions like, não tem, and nada to express nothingness.
But to say somewhere, anywhere, nowhere in Portuguese properly, it takes a little practice. These are not very obvious.
How would you say for example, Let's eat somewhere; Sit anywhere you like; or, She has nowhere to go -?
This is the easiest of the three. Just as we can say something in Portuguese, we can turn that into somewhere like this:
Remember: algum = some... But it's gender has to agree with the subject. That's why it's alguma coisa and it's algum lugar. COISA (femenine) & LUGAR (masculine).
You could have also said: Vamos procurar UM lugar para comer. Same thing.
This one is similar to forming anything: qualquer coisa.
Another way of saying this is: Pode sentar onde você quiser. (You can sit where you like).
But there is another way to express this. Brazilians often use tem para onde + verb to say don't have anywhere to xxx . Like this:
The word order is not important.
Note that the english translation of this last one is actually anywhere. Most english phrases that use nowhere actually get translated into portuguese by other phrases.
The middle of nowhere = No meio de nada.
There's nowhere like home. = Não há lugar como o lar.