Doesn't beautiful = bela and pretty = bonita. Beautiful and pretty are not truly synonyms. IN Spanish bonito/a means "pretty" and also "nice".
Belo/a, Bonito/a, Lindo/a can all be beautiful. But my limited sense/experience is that Lindo/a is beautiful in a lovely way while Bonito/a is beautiful in a pretty, nice, cute way (and belo/a is not used as much but is beautiful in a fine, good way).
Probably not. "Handsome" when used to describe a woman in English means a woman who is NOT pretty but still somehow attractive in an indescribable way. Like when Hank Hill calls his wife "handsome" on King of the Hill.