Learn Portuguese (Portugal): O programa de sobrevivência tem uma tribo na floresta. - The survival show has a tribe in the forest.

Tribo is an exception to the general rule. It is a feminine noun despite ending in -o, which is why it takes the feminine article uma. It is good to memorize this one along with other exceptions you have seen, like a mão (the hand).

Why is the masculine article O used for programa?

Many Portuguese words ending in -ma that come from Greek are masculine. You will see this pattern often: o programa, o problema, o sistema, and o tema.

How do we know to translate "survival show" as programa de sobrevivência?

In English, you can stack nouns to describe something (survival + show). Portuguese doesn't do this; instead, it uses de (of) to link them. It literally translates to "program of survival".

Could I use há instead of tem to say "there is a tribe" in the show?

Not quite with this exact structure. If you use há (there is/are), you would have to change the sentence to say something like "In the survival show, there is a tribe" (No programa de sobrevivência há uma tribo). Here, the show itself is the subject doing the "having," so tem is the right choice.