I need tips

What kind are you wearing? How are they installed? If it's wefted, you should seal the weft before installing. Need a little more info for more advice.

I think it's normal for a few here and there to fall out. Even after installing, some just don't seem to get in there well, so I have that happen.

As far as shedding, that can mean the glue is breaking down, or it wasn't saturated enough. Did you buy pre-bonded ones and install them yourself, or have them done professionally?

If you can't brush it sometimes, that most likely means that it's cheap hair. What hair are you using? Also, things other people do is getting a shower filter, and using sulphate free shampoo. I don't do those and still don't have problems with my hair though. But many others swear by this!! Also, putting on something over your head when you sleep, or braiding it helps it from going all over and getting tangled.

But from personal experience, if you combed it all out and you're just sitting around and not doing much and it's like a rats nest after a few minutes of...nothing...then it's not quality hair!