Please help me！

No, do some reading. Do some playing around with paint. Perhaps before that, try drawing.
You poor thing!

I paint landscapes with acrylic because of the fast drying time and water clean-up. Google William Alexander for some great oil painting lessons. His main themes: " Light on light is nothing. To have light, you must have dark."
"Fire in!"

Get it. Thank you.

I don't know what you're going to say.

"Light on light is nothing. To have light, you must have dark." That means that, if you want a light color to appear light, it has to have a dark background.
"Fire in!" That was Bill Alexander's way of saying "Go for it!" He would take house-painter type brush and basically attack the canvas.
( German accent ) "I vill, I vill take my Almighty Brrrush and I vill fire in these beautiful clouds." That was his way of putting energy in the clouds.