In the old days people learned to paint by being apprenticed to a master artist. they spent years mixing paints, studying the way the master painted, then copying what he did, and finally painting small sections of paintings. It was a long and tortuous route. Today we prefer to get things done more quickly.
But there is so much to be gained by copying a painting from a master. I do this often, and with each painting I learn. I learn composition, I find out how he used colour, I learn about brushstrokes and tonal value. I learn what makes a good painting.
A few years ago I painted this Sorolla. It's a copy of his El baño del caballo. What a master of light he was! And what an interesting composition. And it opened my eyes to see how many colours there are in a white horse!
So, if you want to learn to paint, I really do recommend that you find an artist you like and copy his work. You will learn so much.