had quick look...you might try increasing you DPI or resolution...looks like it’s really low which is likely causing the blurry-ness...If you compare that to the actual text added by Docebo which is clear.

Thank you! I think I chose the largest one possible in Canva. It didn’t help. Can you recommend a size? The video instructions show JPG 290 KB, Dimensions 3508x2480

try saving it as PNG with the highest resolution you can...probably 300 dpi. the overall size needs to be what Docebo specs dictate though, not larger otherwise it wont load.