Learn Dutch: Ondanks het probleem bereiken wij het doel. - Despite the problem, we achieve the goal.

Ondanks is a preposition meaning "despite", so it is followed directly by a noun phrase (het probleem). If you wanted to use a conjunction like hoewel, you would need a full clause with a subject and a verb (for example: hoewel er een probleem is).

Why is the verb bereiken placed before the subject wij?

This happens because of the Dutch V2 (verb-second) rule. The phrase Ondanks het probleem takes up the entire first position in the sentence. The conjugated verb (bereiken) must take the second position, which forces the subject (wij) to move to the third position.

Could I use the verb halen instead of bereiken here?

Yes, you can often use halen (to make it / to achieve), like in the phrase je doel halen. However, bereiken (to reach) is slightly more formal and is the standard, natural choice when talking about reaching destinations or abstract targets like a goal.

Are both probleem and doel always het words?

Yes, both are neuter nouns, which is why you see het probleem and het doel. In Dutch, it is quite common for abstract concepts and targets to be het words.