Must haves for baby

I’m a young first time mom, my family is taking some time to wrap their heads around my pregnancy so I don’t really have anyone to ask for advice. I just have a list of questions that I’d love some guidance on:

1. What was the best baby item you purchased?

2. When purchasing a diaper bag what are the important things to consider? I’m leaning more towards the backpack style but would love opinions either way

3. When swaddling baby was it better to use blankets or the little Velcro swaddlers? I’m not necessarily worried about convenience but what is most effective

4. I’m due in July and want to stock up on baby clothes, I live in KS and our summers tend to be pretty hot but I’m not sure what type of essentials to buy

5. I plan to breastfeed but when it comes to purchasing a pump I have no idea what type of qualities to look for it’s seriously a confusing area

6. We have a tiny apartment and I don’t see a need for a 200 dollar baby monitor but I don’t want to completely disregard them because of the safety benefits- would that be a worthwhile investment?

7. WHY are there so many different kinds of bottles I find it so confusing, what kind did you think was best?

Honestly any and all general advice is welcomed, I give myself a lot of anxiety when I feel unprepared and I just want to have everything I need for baby. Thanks so much!