Glocks are great. I carry a G20. Would not want anything else. Been doing so 20 plus years.
A Glock is a different bird, not to everyone's liking. One thing that gets it noticed, good and bad, is the trigger and the absence of an external trigger block safety.
While the industry moved on to decocking handguns, Glock went the other way.
If you have lunch money in yout pocket, and you want to add an external trigger block safety to your Glock, making it impossible to shoot, unless you want to shoot it by easily removing the safety, order something called a Safe-T-Blok. Available on Amazon.
With it, you increase the level of safely carrying a round in the chamber, to just as safe, or safer, than only having ammo in the magazine.
The trigger safety issue for Glocks is highly contested in forums, and the general consensus is they are not necessary. I feel safety, is never to much trouble.
Enjoy the Glock. Before you pick it up, hit a box store, and get a safe to keep it in.
Holster? I have two. One is soft, and holds an extra mag. Brand is liberty sporting. Some Wal-Mart's have them. I also have a BlackHawk that the gun locks into. High tech. Prefer the simpler liberty that holds an extra mag.