How can I create a line from Line renderer, and keep it there permanently until it was manually deleted?

Hello guys! Im currently working on this 2d unity project for me and my friends, at the moment im using a line renderer to draw the lines on screen.

Once the line is drawn, the line immediately goes away. But I want the lines to stay permanently until manually removed by a button or a tool.

Ultimately I don't think line renderer would be the best option for me at this point,

Is there a way I could make it so where OnMouseDown, it draws pixels across an area and stays there - then using another tool to delete that line?

I would appreciate any help I can get!