Where can I find Galaxy S10+ screen repair kit?

Are you looking for a tool kit or a repair guide? If you are looking for a repair guide, I would suggest looking at similar guides for older Samsung phones as the process is very similar with the exception of the internal components. Samsung uses the same size screws for everything so that makes things a lot easier. My best suggestion is to find a full assembly and just transfer the parts over. This is the quickest and easiest way to repair it. If you are looking for tools, a heat gun (or hair dryer in a pinch), suction cup or any other tool to help create a gap for getting the back glass off, thin picks or playing cards and a number 0 fillips head screwdriver. Curved tipped tweezers and a spudger are also good tools to have.