Helppp if anyone is good in French

Which conjunction best completes the sentence?               peux-tu passer au supermarché tu vas chez le coiffeur. a. que b. quand c. ni d. mais

Ineed french . i am writing sentences i wrote in english in french. could someone check to see if the french translations are correct in regards to linguistics such as grammar? 1. i like the bookstore the best. > > > j’aime la librairie le meilleur. 2. i don’t spend a lot. maybe 30$ dollars. > > > je ne dépenser pas beaucoup. peut-être trente dollars. 3. the jewelry store is the most expensive. > > > la bijouterie est le plus cher. 4. i pay with money. > > > je payer avec l’argent.

Explain what has to happen when you use être instead of avoir for the formation of the passé composé? il an english explanation with steps if possible