You can do a “Item spawner” blueprint which randomly selects items and spawns them in a specified area.
Like this you only have to place that BP at the places you want items to spawn and it will take over everything else. However I would suggest to at least go through the blueprint guides by epic games before you start working on that. If you have no experience in programming you might want to watch some other tutorials about that as well (there are quite a few great guides and tutorials about all parts of it. Just search around a bit on youtube and you should find quite a few things.