If you listen to experienced speakers, it's easy to see some real differences in how they step through their presentation than maybe how you go about giving a talk when you are called upon to speak in public. But it is a good exercise to use every opportunity to listen to different public speakers and learn from them. From speakers who are not effective, study why they are and learn how to correct those problems in your presentation. For speakers who are very good, learn what they do that works and copy their methods without shame. It's all part of learning from each other.
One thing that jumps out when an experienced public speaker is holding an audience in the palm of his hand is that he is totally relaxed up there. That is a calculated relaxation. In fact most of the methods he uses such as his use of hands, the vocal range of his voice, where he looks and how he moves are all carefully planned and part of that presentation and who that speaker is. And all of those things come with time and practice. So if you need a few times in front of a group, or a few dozen times before you can begin to get that relaxed, be generous with yourself and allow that public speaking is the kind of thing that you can read about all day long but you dont get good at it until you get good at it.
One thing that very often jumps out in a speaker who is at ease with his style is that for most of us the idea of a pause is terrifying. But notice smooth speakers often will pause and allow that moment of quiet in a presentation to just hang there. When that pause happens for that other speaker, you may have felt as terrified as if it was happening to you. But not to worry. As you noticed, that skilled speaker uses pauses to create interest and isn't afraid to let his presentation stop for a moment either intentionally or to check notes or make some other adjustment.
The pause is actually a very powerful communications tool that if you can master it, you can use it to make points, add drama or just wake up an audience that may have begun to doze off on you. That is because as you speak along, if your presentation is somewhat long, it is easy for people to be lulled into an unintentional trance of sorts. The mind can wander and that is the condition people get into when they doze off as you speak. They track to the continuous sound of your voice and the melodic tempo that you naturally fall into when you speak in public.
When you begin to use pauses and changes to the tempo of your presentation, you break that natural rhythm of your talk. The pause will jar the audience back to you and they will suddenly be attentive with that "what did I miss" look on their faces. That is a real tool to you to help your audience stay focused and to use particularly when you are approaching a point that is an important part of what you have to say.
Most of us when we are just starting out in public speaking fear the pause in our presentation in the worst way. That moment when you are not speaking and that audience is looking at you and nothing is happening can feel like you are falling to your death. But in truth, all you have done is focus the concentration of the group on you and on your talk. So don't fear the pause. If used with caution and sparingly, it can be a powerful communications tool to help you make your point.