How did the literature, painting and calligraphy works of the ancients spread? There were no publishing houses, online media, etc.

Literature: Before movable type printing, there was woodblock printing, and before woodblock printing, there were manuscripts.

As for the spread of paintings, they basically rely on single works. Later, when engraving and printing came about, it was plate printing. But if you look at the Mustard Seed Garden map, you will know what the printed effect will be - there is no change in the shades of pen and ink at all.

Finally, there is the spread of calligraphy works: they are usually made by stone rubbing, but they can also be simulated by filling in ink with the double hook method.