Most of my website's pages were created with Flash. Since Adobe will discontinue supporting Flash in December 2020, can my pages be converted from Flash to something that will display them properly, i.e., with the "animation" and "navigation" intact? Also, since many small non-computer devices, such as phones, do not support Flash, would they be able to display the converted pages properly?
No you can’t just convert Flash SWF. That’s why Adobe and the browsers makers gave 3 years to do it again. If done with modern apps and standards, HTML5, yes it should work on mobile devices.