I lost my iPad and I cannot find it on « lost my iPhone » app. Is there something i can do

What does it say in find my iPhone? Is it saying offline? If so, no there is nothing you can do. It cannot update its location unless it is online. If it does not show at all, that would imply you never enabled the iCloud account setting for find my iPhone on that device before it went missing.

Anyone can erase an iOS device in iTunes which will make it untrackable. As long as you leave it listed under your AppleID, then activation lock will keep whomever erased it from actually being able to use it.

A device cannot sync via iTunes unless it is plugged in to the computer, or on the same local WiFi network.