You need a 0.6mm Tri Point screwdriver. It is a Y shaped tip. What happened to this phone that it is bent? Why don't you have the screen off so you can get at the screws? Also, you must hold a finger at the end of the screw for more rigidity.
Did you check on youtube for iPhone 6s glass replacement only? You might get some good ideas on youtube. I looked at a few just out of curiosity and some looked pretty informative. Hopefully you can find something to help your situation.
In your picture, it looks like you must have somehow knocked off your home button contacts. Look at the picture in step 7 of the Home Button Repair Guide. Actually you can see these gold contacts in many pictures throughout the guides. There are 2 gold contacts. these contacts are missing on your picture. Looks like this is your problem.
You can get a whole 47 pc screw set on ebay for only 2 bucks. The screw you are looking for will be there. http://www.ebay.com/itm/47-Piece-Full-Screw-Replacement-Set-For-Apple-iPhone-4-4G-USA-SELLER-/161053030805?pt=US_Cell_Phone_Replaceme... 8 Also make sure the silver metal spring on the wi fi antenna cover that the screw goes into is still there and didn't fall off.
You need a new screen lcd/digitizer assembly. There is a guy on ebay who does it for $35 and is excellent. "home_electronics 10" Look him up but it must be a 4th gen ipod. Whatever you do don't have a friend try to fix it because they will probably damage it.