Can I receive texts that were sent when I had mms and group text off? I was traveling and had them off and forgot to turn them back on. Can I still get those outstanding texts?

Depends on the time period, but I would call the carrier and ask them. They are the ones that store and attempt to deliver your messages. I have group text turned off all of the time and that does nothing to prevent texts from being delivered to my phone. While MMS might prevent any media texts, it would not prevent others.