"To look" means to direct one's eyes (intentionally)
I think to understand in depth, let us observe the sentences below:
Look at two boys over there! Can you see them?
I am looking at the sky, but I can not see anything.
Maybe you can see me here again next week, but you should look at the table 1.
Well, if you want to understand in depth about the two words, I suggest you to read and read.
Or find in the related posts below!