While Old School RuneScape is based on a backup of the game files from 2007, it is a separate game that was released in 2013. Everyone starts from scratch in that version. See the Dude... where's my stats? article in the Support Centre for additional information on that.
OldSchool RuneScape is a new game started in 2013 and not the one you used to play, the game you used to play is RS2 which is now RS3, which is why all your items and levels are on RS3.
If you want items and levels in OldSchool RuneScape, you have to play the game and start from scratch like everyone else who has stats and items there, no one got stats or items moved from RS3 to OSRS. If you don't play OSRS, you won't have items or stats there.Hi.