I would say it's pretty difficult to be honest. As with any competitive specialty, it comes down a lot to your board scores and your letters of recommendations. This last year, I believe we had about 10 people match into a categorical general surgery position with another 15 or so matching into a preliminary PGY-1 position in general surgery (a 1 yr contract, requiring you to reapply to the match the next year). Its not impossible, but you really have to be focussed from the beginning and set yourself up for success by studying hard and making connections in the field.
Regarding fellowships. Theres less focus on if youre an IMG or not and more focus on where you completed your residency (community program vs academic). Some fellowships are more competitive than others (Pediatric surgery, CT surgery, surgical oncology vs MIS, Crit care).