Like the title,i can't drawing/and do anything?I checked,all layout is not been locked,but still can't do anything

Well, I'm not omniscient, so without even a screenshot it's hard to say what your problem is, but check that you're not trying to draw on a vector layer. I've also heard of people who actually didn't create or open an image to draw on in the first place and were surprised that they couldn't draw.