I have a 2d black and white hand-drawn artwork like a cat, cow, or ironbox. The lines are of various thicknesses, one line is 1mm, another is 3mm, another is 4mm. I want to make all the lines in my drawing equal in thickness. Is there any software or online tool available to achieve this? Though it is a raster image, I have the tools to convert it to a vector image. I not an expert in drawing or graphics designing.
Auto tracing is possible using most vector software, however it will just trace the image as it appears, and won't help you make all the lines the same width. Some also have centre line tracing, but that also comes with its own set of inaccuracy problems. In reality there is no good way to automate the creation of vector images. There's no one to one conversion of raster images into vector images.
In my opinion, the easiest way would be to redraw the image manually using vector software, such as Inkscape (which is free), or Adobe Illustrator, Corel Draw, Affinity Designer, etc.
In the example below I used Inkscape.
Import the raster image into the software, lower its opacity. Then using the Pen tool (Bézier tool), redraw all the lines by tracing over the top of the raster image. You can also use the Ellipse tool to create circles. When you have finished, delete the raster image.
You can then select all the paths, and change the stroke width using the stroke settings in the software, or change the stroke color, etc.