Questions & Answers about Мы завернули картофель в фольгу и поставили его в духовку.
They are both past tense, plural forms.
- завернули = we wrapped
- поставили = we put / placed
The ending -ли shows that the subject is мы (we), so the action was done by more than one person or by a group including the speaker.
Compare:
- я завернул = I wrapped
- она завернула = she wrapped
- мы завернули = we wrapped
Russian uses the perfective aspect here because the sentence describes completed actions with a result:
- the potatoes were wrapped,
- then they were put into the oven.
So:
- завернули is perfective: the wrapping was completed
- поставили is perfective: the placing into the oven was completed
If you used imperfective forms like заворачивали or ставили, it would sound more like describing a process, repeated action, or background action rather than a finished sequence.