Do you have to reside in a state for a certain period before able to file a chapter 7? We live in INDIANA now but moving next week to Pennsylvania.

Yes, you must file in which ever state you have resided the longest during the 180 days prior to filing your bankruptcy.  However, if the filing state is an opt out state (meaning it does not follow bankruptcy code property exemptions but rather it's own state law exemptions) then you will have to follow the state where you have lived the longest period of time over the course of 1070 days, which usually means the prior state where you resided.  If you wait 91 days after you move to Pennsylvania and then file there, Pennsylvania will be the proper venue, but you will have to use Indiana exemptions.