Level Blueprint, Hello World!
Level Blueprints are used for scripting level-specific events within maps. It's a specialized type of Blueprint that acts as a level-wide global event graph. Each level in your project has its own Level Blueprint created by default that can be edited within the Unreal Editor, however new Level Blueprints cannot be created through the editor interface.
To create a Level Blueprint for the current level, you need to select the Blueprint button from the toolbar. In earlier versions of Unreal, before version 5, you could see a toolbar button called "Blueprint". At this time of this blog post, version 5.0.2 still has this three white dots button to select. Seems like it's a placeholder to be updated with a newer graphic later, just assuming. Look at this picture below:
If you select the three white dots drop-down, you'll see "Open Level Blueprint". Select that.
A new window Level Blueprint Editor will open with the same name as your level. Go ahead and dock that with the main window to keep things all together.
In the event graph canvas, here we can write our blueprint code with nodes. Right-click on the event graph canvas and an "All Actions For This Blueprint" window will pop-up. This pop-up window shows all the possible functions and events that you can use to "Visual Program" your game with. Now let's make a "Hello World" program. In that window pop-up, search for "Event BeginPlay". Make sure it's selected underneath the search bar and press enter. You should have a new Node called "Event BeginPlay" on the event graph canvas. Now search for "Print String", select it, press enter. Now a new Node called "Print String" should be on the canvas. Left click and drag out the white line from the "out exec pin" of the "Event BeginPlay" Node and connect it into the "in exec pin" of the "Print String" Node. In the "Print String" Node's "in string" input box, type in Hello World. All this should look like this in the below picture:
In the top left window in the toolbar of this Level Blueprint Editor, make sure the compile button has a green check marked, if not press it to compile the Blueprint. Also press save to save the blueprint changes. Press the green play button and you should see "Hello World" displayed temporarily in the top left of the game's view.