Experience life as it is

The only thing you can be sure about is perceiving the "here and now" even if it was a simulation/hallucination/dream/the real experience. I don't think it's that important to know if this is a simulation or not, I think knowing it ruins the experience. You are experiencing something you can't know for certain what it is, so live like you don't know and make decisions so it doesn't cause regrets if any of them were the truth.

If you took life too seriously you'd regret it if this turned out to be a dream/simulation. 

If you lived life too playfully you'd regret it if this was the real deal and everything mattered. 

If you committed atrocities you'd regret it if hell existed. 

If you lived your life in the fear of God(s), you'd regret it if Heaven didn't exist.

If you lived like there wasn't an afterlife, you'd regret it if there was. 

If you lived like there was an afterlife, and it turned out there wasn't you'd be missing the only experience you ever had in the hopes of having a better one next. 

If you deprive yourself of pleasures in this life in the hopes of saving it all for the next life, it would definitely suck if it turned out that you were doomed to live this very life over and over again. 

If you indulged yourself too much, it would also suck if the next round is a counter balance to your previous one. 

Just live your life the way your are fine with. Make the decisions you can live with (even after death). So when the truth is revealed you can say "it was worth it" regardless what the truth shall be. Experience life to the best of your knowledge while enjoying it. 

PS. You can always take comfort in the fact that you didn't know, as long as you are honest to yourself.