Girls are not able to have orgasm after having circumcision, right?

U R mostly correct. Stimulation of the clitoris is how 90 - 95% of females achieve orgasm. Female circumcision involves ampuation of the clitoris, so no orgasm or much sexual pleasure is achieved. Hence female circumcision is in fact mutilation and banned in all civilised counties. An occasional mutilated female might be able to achieve orgasm via the g spot, located in the front of the vagina.
Yes and no. In this country, girls don't get circumcision. Circumcision on women is considered a form of genital mutilation in the usa. It is common in other countries. It is used to prevent sexual arousal. It usually causes extreme pain with intercourse. No woman should ever have that "procedure".