VALORANT_BR - GL mwzera destroys Veroneze in the showstoper duel

I played very little of valorant and I'm really bad. I panic when shooting and using my ability. What agent is easiest for begginers and how do I stop panicking?

So is there any reason why shotguns in this very comp focused game don't have fixed pellet spread like in games such as Apex Legends? Do they fear it would make shotguns too powerful?