1. Poser comes with characters - a man, woman, boy, girl, and baby. Figures like Victoria 3 from DAZ are more realistic than the Poser people. A lot of people use them, so there's lots of stuff for them, free and for sale. But they take more system resources, so if you have an older computer or want to do animation, they might not be for you. Also, you cannot use them in the Face Room. That only works on the Poser 5 people.

If you buy Victoria 3, you have to get the base, the body morph pack, and the head morph pack. You will also need textures and clothes, but you don't have to buy those at DAZ. Don't buy hair at DAZ. Instead, download free hair from Japanese sites such as Koz's.

http://digitalbabes2.com/

As you can see, this will rapidly get pretty expensive if you buy more than one figure. Besides Vicky 3, there's the male character, Mike 3, two young-looking characters, Stephanie Petite and David, the young teens, Luke and Laura, the Millennium Kids (preteen and preschool boys and girls), and the Millennium baby.

If you do decide to buy the DAZ figures, sign up for their
"Platinum Club." The discounts you get for being a PC member will actually save you money if you buy more than one figure (and their morphs, textures, clothes, etc.).

2. Click the double check mark at the lower right of your screen. Do not double-click on the library thumbnail. That will replace the current figure with the new one, as I suspect you have discovered. :-)

To pose them...you can buy poses, and there are some you can download for free. There are hand pose sets that make it easier to do "holding hands" poses. But in the end, you really have to learn to pose the figures yourself. You might want to turn off inverse kinematics. Often, it's easier to use the parameter dials to move the body parts, instead of the mouse.

3. Click on the "Poser forum" banner at the top of this page. There's a FAQ there. Also, search for tutorials by Dr. Geep. There are some other good sites for beginners out there; I'm sure others will chime in on this.

4. Definitely Koz's site, as mentioned above.

What exactly are you trying to do? Do you need to make the characters look like specific people? What type of art are you hoping to do?