hi i'm in year 13 and i can say for a fact that your teacher is wrong loll. i think it's one of the easiest shakespeare texts to study! we have 2 english classes and the other class study Hamlet. it's so long, sooo much longer than A&C and my friends in that class really dislke it + my teacher specifically chose antony & cleopatra because you can always write about the same stuff for any essay question and use the same AO3 and AO5 for all your essays! i'm not sure what you've covered so far in the play but i can genuinely tell you right now that it's not difficult at all
what's your exam board btw?