Learning to play the guitar will take time, commitment, and dedication. You cannot become a master of music overnight. Learning to be a good guitarist requires not only muscle training, but also ear training. Arguably the biggest part of music is understanding it. You must be able to hear what you're going to play in your head. This isn't to say that physical ability isn't important, but many people will spend hours on physical training, but very little on ear training.
So if you're a new guitar player you probably have many questions. The first thing you should do is figure out how to hold your pick properly. Many beginners will make the mistake of holding it wrong and it will stay with them. This is a bad habit because it can lead to a lot of dropped picks, and of course this will make you sound bad.
So once you figured out the basics of the guitar and gotten fairly comfortable with it, you are obviously going to want to start learning songs. Simple guitar songs are everywhere. You will be very surprised with how not complicated a lot of music is. This is great because it can keep your interest at the beginning. You will not have to feel like you're incapable of playing anything musical. There are so many easy guitar songs out there for you to play at the beginning.
You also want to start expanding your chord dictionary almost immediately. There are about a dozen open chords that you will need to know to play simple guitar songs. These are of course G, C, D, E, A, and a few others. Once you know these chords well you will be able to play many different songs.
So if you're just starting to play the guitar, be sure that you stick with it. Don't get discouraged if you can't play super complicated music right off the bat. These are the kind of things that take time to do. Find some simple guitar songs and learn how to play them properly. You will find that your expertise will develop over time.