My First Garden

First picture is my broccoli, I planted it four weeks ago. I was wondering if it's normal for it to be growing tall like this instead of bushing out? My seed packet seemed to indicate it would be ready for harvest much sooner than I believe it will be considering there are very few leaves and no crowns appearing…

The second picture is of my yellow onions. The packet said to plant several seeds every inch, so they look very obviously crowded to me. How long am I supposed to wait to thin them out?

The third picture is of my chives. I in all honesty just don't know if they look healthy or not.

Thanks so much for any help. Let me know what info I should be providing!