So your phone doesn't show an image/or backlight AND touch is not working? Are you sure it is a drop, not liquid damage? Back light, image, and touch are 3 different functions with somewhat different "circuits" on the board. They may both be damaged, but more often it is just one of the 2. I'd start with the following:
- There are 3 screen connectors on the board. Clean them with a cotton swab dipped in 90%+ isopropyl alcohol. Then try reseating your screen and re-booting your iPhone (press & hold home + power buttons for ~12 seconds straight then restart your phone).
- If no change, remove the black film (very carefully) around those connectors on the board and look under a magnifying glass for missing/broken/part removed components.
- If you see nothing wrong, try a KNOWN GOOD display, something that you know for sure works on a different device. OR transfer your logic board to a known good phone. Let us know what you find out at this point.