Learn Portuguese (Portugal): Instalei o software imediatamente para resolver o problema. - I installed the software immediately to solve the problem.

You could say: Como queria resolver o problema, instalei o software imediatamente. (Since I wanted to solve the problem, I installed the software immediately.) When como is used as a causal conjunction meaning "since" or "because", it almost always goes at the very beginning of the sentence.

Why do we use para resolver here instead of a different preposition like por?

To express purpose or say "in order to" do something, Portuguese uses the preposition para followed by the infinitive of the verb (here, resolver). Using por instead would sound like the problem was the reason you were forced to do it, rather than the goal you wanted to achieve.

Problema ends in an "a". Why does it use the masculine article o?

Words of Greek origin that end in -ma are usually masculine exceptions in Portuguese. Other common B1-level examples include o programa, o sistema, and o tema.

How is the adverb imediatamente formed?

To make an adverb out of an adjective, Portuguese takes the feminine singular form of the adjective and adds the suffix -mente (which is just like the English "-ly"). The adjective is imediato, its feminine form is imediata, which gives us imediatamente.