What do I do

I found an abandoned car in a driveway on my neighborhood it’s been there for about 3 years now and I went to look at it I did it at midnight and it’s was really Erie with a kids backpack and the keys in the ignition it had had a flat tire for about 4 months I watched it during the day and the house it is at has none living their with the car unlocked I (stupidly) reached in and grabbed the back pack and there is some legit logs of a experiment on a kid or something do I turn it in to the cops? I looked up the plate number and found a phone and address that’s for Iowa (I live in Louisiana) im kinda freaked out whenever I think about it