Writing in omniscient point of view is easy to begin with: you use third person (he, she, it, they) and you can see all of the character's thoughts and emotions - not just the main character.
Of course doing it smoothly and with grace is more challenging. I find reading novels with omniscient pov the best way to figure it out. If that was a question, I hope I helped!
βIt's necessary to have wished for death in order to know how good it is to live.β β Alexandre Dumas, The Count of Monte Cristo
I just recently started writing like that. It can be challenging at first when trying to figure out how to do it smoothly. Like Suzanne said, reading books written in omniscient point of view is one of the the best ways to figure it out
How can I be king of the world? Because I am king of rubbish. And rubbish is what the world is made of. — Kate DiCamillo, The Miraculous Journey of Edward Tulane