Desktop Publishing Software Resources

Hi, I'm looking to switch from Adobe. I'm also getting ready to create a second kids picture book and read that Affinity Publisher cannot create the e-files required to upload the book to Amazon's KDP ie. epub or mobi files. I'd greatly appreciate any input for this please, otherwise I'm ready to purchase the program, except I'm not sure what I would do if Publisher cannot do this function. Thank you (hoping and praying for quick answer)

There are applications that are simply not possible in a platform like Canva, compared to someone going into Adobe and building from scratch. What are some ways around this? Do you think using multiple platforms is wise, or should Canva be used as a backup tool in an effort to actually learn graphic design?