I took several photos of a drawing that a friend had made, but the quality of the photos is not very good, so I need software that can produce enhanced images by combining a stack of images of the same scene that were taken during a short period of time.
+1 from my side. I use Siril constantly to improve the signal-to-noise-ratio of my astro photos.
But I highly doubt that the photos OP described were shot in RAW and under the exact same conditions