Breakdown of Θέλω να γίνω καλά σύντομα, γιατί δεν αντέχω άλλο αυτή τη ζάλη και αυτόν τον βήχα.
Questions & Answers about Θέλω να γίνω καλά σύντομα, γιατί δεν αντέχω άλλο αυτή τη ζάλη και αυτόν τον βήχα.
Because γίνομαι καλά means to get well / to become well, while είμαι καλά means to be well.
So:
- Θέλω να γίνω καλά σύντομα = I want to get well soon
- Θέλω να είμαι καλά = I want to be well
In this sentence, the speaker is sick right now, so the idea is a change of state: from unwell to well. That is why γίνω is the natural choice.
Here καλά functions adverbially, meaning something like well.
Compare:
- Είμαι καλά. = I am well.
- Θέλω να γίνω καλά. = I want to get well.
Even though καλά is also the neuter plural or adverbial form of καλός, in expressions about health it is the normal form.
So you should learn γίνομαι καλά and είμαι καλά as very common set phrases.