Hello there I have a problem!

HelpmePlease,

How about View>Hide Artboard?

Can you please upload a picture how I can do that?

Create a new Illustrator document the size you want and place your texture image, rather than opening it directly.

Whenever I open Adobe illustrator and i click on 'open' and put a picture 'that has a white background'that black line square appear, i want to remove it.

What do you mean when you say you open a 'white background picture'? Are you opening a white raster image? Why?

edit: I see, it's a texture, not pure white.

Illustrator files have an artboard, which is your export area, and a pasteboard or canvas, which is the entire working area.

When you create a normal AI file, you define the artboard size.

When you open a raster image, Illustrator uses the last used artboard size. That's the rectangle you are seeing.

Create a new Illustrator document the size you want and place your texture image, rather than opening it directly.