Hi, welcome to WC and the oils forum! Best first step... if I had to choose one, it would be drawing fundamentals.
By practicing your drawing, you'll train your eye how to "see", you'll learn form, composition, line, and VALUE.
While you are practicing your drawing study color theory. Learn the color wheel and how different colors interact with each other. Learn about chroma, vibration, value
, and hue. You'll also learn about light, and how it has color as well as color in shadow.
I know this doesn't sound as exciting as playing with paint, but there is quite a lot of study involved as well as lots of practice.
Above all, have fun!! Art is a journey, be kind to yourself and congratulate yourself on all of your efforts.