Hello Player_003, thank you for posting your question.
There are a couple of ways to go about this:
The most common is by using a Game Instance. There are quite a few brief tutorials on this subject if you would like to review one.
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Mathew Wadstein: HTF do I? Save Variables between Maps ( UE4 )
Additionally, I would look into SaveGame classes for maintaining your values across the game.
I hope this helps.