How can I give a block an nbt tag to store info needed in more than 1 procedure?

I've been trying to store info in a block that I can access and change with multiple procedures. I want it to function like a comparator: You click on it and then it it is either in one of two modes. I have the checkmark asking you if you want to enable the block entity turned on but nothing happens. My test procedure is just the:"Set NBT logic tag "OnOff" of block at x:x y:y z:z to "true" if it has block entity" block being triggered when the block is right clicked followed by a block that sends the value of the nbt tag into the chat. pls help me why is this not working i cant even find any info that isn`t two years outdated