You do not need long fingernails to play guitar. In fact, it's best to keep your fingernails short! As for the callouses, these may be unavoidable. If you would like to avoid them as much as possible, ask your guitar instructor about lowering the action of your guitar (the action is the distance between your strings and your frets) so that the frets are easier to press down on.
When you play the right note or chord, you will hear it. It will be a pleasant sound, it will be clear and won't have any blocked string sounds (unless it needs to, but you'll get to that later). To play a note or chord correctly, you have to get your fingers in the right position and press as hard as you can on the frets; it will become a habit if you practice enough.
The simplest answer and the one that no student that ever wants to hear is practice. Changing chords is the process where many beginners fail, and quit. But after that, the rewards will be simply impressive. There are a few tricks to get a chord transition to happen faster. Use a metronome: Set it on four beats and set it as fast or as slow as you want. Then get a chord in your mind, say D. When the metronome reaches its last beat, press down the strings. When it happens again, strum it and let it free. Then again. Do this 10 to 20 minutes a day and in less than a week, the chord progression will begin to sound much better.
"We come to you for private music lessons! My father used to sit in his car, in front of my teacher's house for 2 hours a week when I was growing up, with the hot New Mexico sun beating down on him. Having a teacher come to your house and teach the lesson in your home saves up to an hour a week of your time round trip. With our business model, while your child is taking lessons, you can prepare dinner, help another kid with their homework, finish up work, or catch up with friends and family over the phone - anything else but wait in a studio for the lesson to finish, or be stuck in traffic. Our teachers are highly qualified. They all have music degrees or equivalent work experience, and they are positive and professional with their students. I love teaching music lessons. It is extremely rewarding to teach people new things, and cultivate artistry and musicianship in another person. Kids in music lessons are more confident in band, and they have a network of friends and band members they will cherish for a lifetime. Our teachers have passed a background check, and they have made it through an audition screen. We don't hire just anyone - we make sure they understand music theory, and that they are top notch players. Invest in yourself!"

These lead guitar lessons cover everything you need to know in order to get started with playing lead guitar. You'll learn things like: proper hand technique, the Major Scale, the Major Pentatonic Scale, the Minor Pentatonic Scale, bending technique, vibrato technique, legato technique (hammer-ons and pull-offs), and even how to play your first guitar solo! So, whether you are brand new to playing lead guitar or just want to sharpen your skills - these lead guitar lessons will help.