The most important thing about being still here when the AC and the mark of the beast shows up is that you've built up your faith in the Lord, continually abiding in Him, not so much prepping and stockpiling food, etc. unless God specifically tells the individual believer to do that.
The building up of faith and abiding in the Lord is the most important because He is our actual protection and provision. He will provide until it's time to either die for the Lord (or just from natural causes - that's up to God) or He comes to pick us up.
When I first had come to the conclusion that the rapture is Post-Trib, I was honestly very scared. I started looking up prepper videos to learn how to grow my own food and purify water. I even looked up solar panels for energy. But doing all that just made me more anxious!
God had to calm me down and He laid it on my heart that I'm focusing on all the wrong things. So what am I supposed to do? Bible say to endure to the end (Matthew 24:13) in regard to the last days. So the MOST IMPORTANT thing is to build up my faith and fellowship with the Lord. So I prayed about that to the Lord and I learned it is all about constantly submitting my all to Him in all things.
God started putting events in my life where my faith was being challenged. At first I thought maybe He was angry at me, but God corrected my thinking on that. He was allowing difficult things into my life in order to put into practice being faithful to Him and trusting Him through them!
For example, I'm not making as much money as I used to and I've gone through situations where I just didn't have enough money for some sort of emergency. I learned to completely trust God for provision -- AND HE HAS COME THROUGH
EVERY TIME!!!
I've also come across people who have been bullying me. I was upset that God was allowing them to continue to do that and without repercussion, but God had told me to reread the parts of the Bible where His servants were greatly persecuted (which was often, actually). He laid it on my heart that in order to be strong in the coming Great Tribulation, I have to exercise my faith in Him in the adversities He's allowed into my life right now. And because He explained that to me, I've been able to handle these adversities so much better!
So yeah, right now I'm not stockpiling any food or gun or ammo or energy. I'm building up my faith in the Lord to endure to the end.
PS - The Bible says that most Christians will die at the hand of the AC - mostly from refusing the mark of the beast. There's also nuclear wars and natural plagues too. I'm not anything special so I'm pretty sure I'll be one of those Christians who die, so I don't see any point in stockpiling food.