Now, this is how to handle a gun safely. Keep your finger off that trigger until you actually shoot. Period.
Once, decades ago, I was assigned duty as one of a select group to stand guard on nuclear weapons. I will skip the details. Part of the requirement was to qualify on combat shooting with the .45 Model 1911. We spent some hours on a Marine Corps base being trained by a couple of Marine sergeants. In my mind, the best in the business. Although I am certain that tactical handgun operations have evolved a great deal since then, some basic safety rules still apply.
Always assume any gun is loaded. It doesn’t matter if you have watched a person unload one, treat it as a loaded weapon anyway. Check it for yourself. Visually and tactilely. Put your finger in there and verify there are no rounds in it. The closest I came to being shot was when relieving the watch. I was going off watch. I dropped the magazine, cleared the weapon and put the ejected round and magazine on the small working desk we had. I doubled checked to ensure the pistol was not loaded and handed it to my relief with the slide locked back. Then I made a mistake. I did not watch to see that my relief properly checked and reloaded the gun. I was writing in the log book when he fired a round about a foot away from my head. I whipped around. He was frozen, his finger still on the trigger, staring wide-eyed at the pistol. I reached out, grabbed the slide and barrel firmly and with my left hand got the web between my thumb and finger jammed between the rear of the frame and the hammer. I took the gun from him and unloaded and cleared it again. No need to relate what happened next. It wasn’t pretty and needless to say we lost a member of our watch team.
Some would call that an ”accidental discharge”. I call it stupid and negligent.
Another way to be stupid with guns is to forget that you are also responsible for any bullet that leaves your gun. Do not point a gun at anything you do not intend to shoot except for a safe area of ground. Don’t carry a gun pointed at the sky or a ceiling. a bullet that goes up, unless it lodges in an innocent victim above, has to come down. There are instances of people being killed or injured by bullets falling from the sky.
Physics. There are a number of internet videos documenting that not understanding basic physics can get you or someone else hurt. A fired projectile can rapidly change direction depending on what it hits. If you shoot at the wrong thing, it can come back for you or someone else. Find the YouTube video of Mr Stupid shooting a .50 cal at a vertical steel plate. If that returning round had been a half inch lower the result would have been too bloody and gruesome to have made it on YouTube.
Lastly, do not attempt to teach a novice how to shoot without a lengthy, hands-on gun safety lesson first. Otherwise, you will be putting them, yourself and any bystanders in danger.
Guns are dangerous weapons. They are supposed to be. Treat them that way.