Let’s say I wanted to say “This is what I need” in French. In this case, I know to use the “ce dont” construction, and I’d say “C’est ce dont j’ai besoin ”.
However, I’ve never learned how to deal with a situation where a verb takes an “à”, such as “penser à”. Like if I wanted to say “this is what I’m thinking about”, google translate is telling me it’s “c’est ce à quoi je pense”, but I don't know if that’s right or not.
C'est ce à quoi je pense is 100% correct.
Note that if you want add some emphasis on the "this" component, you can also say:
C'est à ça que je pense.
C'est à cela que je pense.
That's correct. "To think about sth" is translated by "penser à qqc". There is a difficulty, though. If you say instead "I'm thinking about it." you do not say (because it's wrong) "Je pense à le."; the equivalent of "about" is, so to speak, absorbed into the pronoun, which is not "le" but "y" and you say "J'y pense.".
