Make two bp, BPA and BPB.
In BPA put a new bool and click the eye:

Compile, save.
In BPB, make a variable, of type ‘reference to BPA’ ( also make it public ):

Now drag 1 of each into the level. When you click on BPB, you can set WHICH BPA you’re talking to:
Now, when you play, BPB will be able to see the boolean in BPA, like this:

