Welcome! This is a great site, and people are more than willing to help give advice. There are some people who are fairly new to smoking (like me) and some real experts. All have had success and failures at cooking, and all are willing to share what they have learned.
If you are starting new, I would recommend starting with something simple and easy to use. Get the feel for smoking, have some success, have a few failures, and grow from there.
First, determine what type of smoker you would like to build, and how much you want to spend. Take a look at some of the forums on this site and see what others are doing. Ask questions and get a feel for what is right for you.
I started with a cheap Brinkman charcoal smoker, then bought a Masterbuilt electric smoker, then a Weber Smokey Mountain 22". I now own 4 smokers and 3 grills, and I use all of them for different cooks.
I use the Masterbuilt electric when I want a simple cook but don't want to spend a lot of time checking temps. To me, the electric is the easiest to use, and the food always turns out good. I use the Smokey Mountain when I want the best quality. Nothing beats the flavor of cooking over a nice bed of coals with a few wood chunks adding smokey flavor and a beautiful smoke ring. Plus the Smokey Mountain is very easy to use and maintain temperatures. My Brinkman is smaller, so I use it on RV trips with the family. It's a little harder to control temps, but it does a nice job of cooking, it's smaller, and I got it for about $40, so I don't mind if it gets banged up when I travel. I have one smoker I use only for cold smoking. I'm also planning on building a WSM Mini and want to eventually build a larger, heavy duty cooker too. (this can become an obsession)
My point is that there are several options available and all of them are capable of cooking great food. As you build your smoker, decide what you want to invest, how you want to cook, and go from there.
Good luck and welcome to the forum!