Okay, you are really close. 3D printing is a bit tricky at this point. Lets start with the easy one. The first layer of the middle end part is way too close. That first layer is by far the hardest to get right but once you know what to look for it’s easy.
You should just be able to see each individual line, yours is kinda smeared.
The other stuff, is a bit more complicated. One at a time.