In this knowledge is nested the fact that you are Created. If your source is Eternal Life, then you too are eternal life. You do not need to discover meaning because you recognize that you ARE meaning. You realize that you do not have to define who you are because God already did that. You realize that you do not have to defend who you are because God Created you eternal.
Nothing can change that.
If God is real, then acting upon that knowledge can only bring greater understanding. From that perspective it does not matter if you believe in God or not. So each option is totally available to you. If nothing has any meaning anyway then you can assign your own meaning to things. You can just do what you want.