What fixed-focus lenses do you usually buy?

What kind of lens to buy depends on the specific shooting needs and usage habits. Since you ask such a question, you should have just come into contact with the headgear and standard change for photography and camera. According to your camera model, you can buy a cheap entry calibration (generally 50 or 35 focal lengths, depending on your camera model) or a cheap fixed-focus lens with a medium and long focal length (narrower viewing angle, easier for beginners to control and easy to shoot), which can make you intuitively feel the advantages and characteristics of fixed-focus lens, and it is also easy to cultivate a sense of lens, which is also beneficial to further photography learning. If you really find that you don't like it, there is nothing to lose by using such a cheap lens. After all, many people actually hardly need to concentrate.