I want this to be red lines, can I do this with pattern fill?
I need 4 steps to do that:
1st, Create a shape.
2nd, Fill with pattern which you like.
3rd, Drag it onto canvas from layer list to create a new pic.
4th, Fill that pic with any color you like.
You can definitely use any pattern fill you’d like, including a red version of that one you have. However, pattern fills in Sketch are bitmap images. That means you’ll probably have edit the original image and change it to be red. If you don’t have the original, you should be able to use Sketch to create a red version, export it, then reapply it as a new pattern fill.
Either that, or recreate it as vector objects, making them easier to edit.