Here's a quick primer to get you started. Expect spend many, many more hours reading up on it.
For "Drive", you have:
For rails, you have:
Everything listed (belts, screws, rails, etc...) comes in different sizes. A small 3D printer might use 8mm rails where a big professional CNC machine might use 30mm rails.
Everything above comes in different grades. In general, you have cheap no name Chinese clones on Ebay and Amazon, quality Chinese products, Taiwanese, and then western made stuff (American, German, etc...).
Most hobbyist want the hobbyist want the Tiwanese stuff (e.g., Hiwin), but buy the no name Chinese stuff because of a price. For example, A 1000mm Chinese linear rail with 2 blocks might cost $75. A Taiwanese (e.g., Hiwin) might be $350. A German made rail will be around $1000 (For a single rail and slide). Most reputable Chinese CNC makers (e.g., Blue Elephant) use the Taiwanese stuff.
Putting the stuff together.
The cheapest and easiest option is belts and aluminum profile slides. That why you see them on most hobby machines. But, it comes with major trade offs. Professional machines and high end hobby builds use Ball Screws and / or Rack and pinion for the drive (ball screws always on Z), and use profiled rails.
The PrintNC uses 20mm profile rails, and 16mm ball screws. That's a good starting point for your build. If your build weighs less than 1000 lbs, there's very little reason to go up to 25mm rails or longer. If your build has a run longer than 4', you will however need larger screws, rack and pinion, or a more exotic solution. Screws whip when they get long.