Well, it looks like you need to move this code to the pickup, and on the pickup have it get player character, cast to the player_bp, and add to the count there. You will want to do something to limit distance, touch would be the easiest because on the item you can have it use “On Event Start Overlap” to do it, increment your count on the player, and finally destroy the actor at the end.
Another problem is that it looks like you’re adding to “Crates left” on the closest “Long Crate” to the player, and then deleting that crate, meaning the change of that variable doesn’t matter. If you want to keep count of things you should store them on your player, game instance, or game mode because those will be persistent.