Why can't I draw on a layer in adobe after effects?

Question

Adobe After Effects

hello, I created a shape layer and I want to draw something on the layer, but when I select the brush tool and try to draw, some transparent squares are drawn on the layer and disappear, do not tell me what's the matter?

Answer 1

Transparent squares - this is most likely you just draw in the alpha channel, on the paint panel, select instead of Alpha -> RGB channel.
And you most likely disappear due to the fact that you draw somewhere in the middle of the timeline, brushes in AE again depend on time. In the same panel, find Duration set to Constant, and draw with a zero timestamp, then nothing will disappear.
In general, Google will help you, look for video tutorials on this topic.