Can I be ordained without going through Seminary?
No, even if one knows all about the Catholic Faith and knows all the prayers of the Mass. The course of life at the Seminary is far more than the classes and the Mass. The whole body of liturgy, courses, work, and prayer, all in a sacred environment and under the watchful eye of experienced spiritual directors, contributes to form the heart and mind of the candidate for priesthood. Whether or not he is aware of it, the Seminary changes a man and forms Christ in him, as long as he maintains a docile, humble attitude. The formation process has developed over millennia in the Church; bypassing these normal channels would be gravely imprudent.
In addition, the ordaining bishop is responsible before God for the priests he ordains, so he wisely refuses to ordain everyone who asks for orders willy-nilly. He needs to make certain, by the testimony of the Seminary professors and especially the Rector, that these men are worthy of the grace they are about to receive. The long Seminary formation gives them a chance to evaluate the seminarians.