it isn't difficult if you're listening to songs, watching movies, writing and working with someone if you're trying to talk to someone the Spanish language, there are also many online courses for learning Spanish

It is not difficult, but you must have interest and discipline, people now have many tools for learning any language. So, go ahead, find some friends and start practicing.

depending if you have the oportunity of speak every day. I supose that for english the the time of verbs is the most difficult thing. But at the end, it´s hard to learn any conversational language, everyone have slangs, double meanings..