Tryed every step on apple to turn on my iPhone it just black

The "Up, Down, Side" instructions require some precision:

• Press and quickly release VOLUME UP

     then

• Press and quickly release VOLUME DOWN

     then

• Hold the SIDE button until an Apple logo appears (15-30 seconds), ignoring "slide to power off" if it appears

The operative word here is QUICKLY; and try it a couple of times, the timing is a little tricky. If done correctly this will always work unless the phone has a hardware problem. 

Force restart is very specific. Follow what I explain below EXACTLY:

1. Press and quickly release volume up button
2. Then immediately press and release volume down button
3. Then immediate press and KEEP HOLDING the side power button. KEEP HOLDING it past the swipe to power off. KEPP HOLDING after the screen goes dark. KEEP HOLDING for however long (could take 20 to 30 seconds) it takes till you see the Apple Logo - Then let go

That happened to me before and My phone was still under warranty though, and they just gave me A refurbished phone instead.

If it stays black, it’s probably just a defect, but if for some reason multi colored line or lines appear after a week or more That usually happens if your phone was dropped too many times