I recommend that you learn about switches and self switched. The tutorial in my signature (made by Andar) contains all the necessary information about this. On top of it, if you want to learn by doing, you can let the engine generate a chest event on its own by selecting a chest event and take a look at the commands used to make that.
For that specific example, you can right-click on an empty tile on the map and choose Quick Event > Chest. That will set it up for you with the animations, direction fix, message, giving the item, then switching to a new page so it doesn't keep repeating. Create one and try to understand how it works, then you'll be able to set up other types of events (not chests) that do similar things.
Hey @Pharonix, just wondering what you're up to lately and if you've had an opportunity to check out the LTBS thread in the past few days...(a couple of us could really use your expertise). Hope you are well and Happy Thanksgiving!