Although it doesn't show it on the chart, most P&S cameras are the 1/2" size or so, and some bridge cameras are as well. A few higher-end P&S (enthusiasts' compacts) are 1" and so are some bridge cameras. For instance, the Sony RX100 series of enthusiasts' compact cameras (a little too large to really be called a pocket camera and a little too sophisticated to be considered a mere P&S) are 1" and so are the bridge cameras in Sony's larger RX10 line.
There are also compact cameras which are actually APS-C or full-frame -- not too many out there, but a few.....
ILC (interchangeable lens cameras) come in DSLR, m4/3 and mirrorless flavors. Lenses usually range in focal length from around 10mm (very, very wide-angle and into "fisheye" territory) to 800mm -- the big, expensive bazookas, with everything in between. Prime lenses are one focal length, whereas zoom lenses are multi-focal length.
35mm is a very popular focal length, as is the "nifty 50," and both are often used as "standard" lenses. Everyone has his or her own preferences in focal lengths but sometimes it takes a while to figure out just what one really does love to shoot and towards which focal lengths and range the photographer tends to go, time after time. Of course certain types of shooting rather dictate the focal length and type of lenses one chooses, too. A wildlife shooter is going to go for that long 600mm or 800mm bazooka while a street photographer might prefer to stick with 35mm or even wider. Someone who really likes to get up close and personal with his or her subjects is going to want a dedicated macro lens. If one does a lot of shooting indoors and/or under low light conditions a "fast" lens (f/0.95, f/1.2, f/1.4, f/1.8) fits the bill. f/2.8 is considered the "standard' speed, so to speak, for lenses: not too fast, not too slow.
An advantage of purchasing and using a zoom lens is that one can get several focal lengths all in one without needing to change the lens, but the price one pays for this is that often a zoom lens is variable in its speed, rather than, say, being a constant f/2.8 throughout its ranges. Usually those speeds are fairly slow, too, which really doesn't matter much in good lighting but can be a hindrance if one needs to shoot in low light conditions. Often "kit" lenses will have smaller apertures (slower) and be variable, which makes them less expensive. These often come bundled, either one or even two lenses, with camera bodies meant for the beginner or the consumer. Many experienced photographers prefer to purchase their cameras as "body-only," and then they select the lens(es) that they want to buy and use with it. In the long run this can save a person some money, as they can choose a higher-quality lens or two right from the get-go and not have to mess with "kit" lenses at all.
Thankfully these days there has been much improvement in ISO so that we can often shoot at much higher ISO levels than we ever could have dreamed of with film or even when digital photography was first coming into its own. That helps significantly, especially when shooting in natural light, low light, etc. Even at that, though, it is still considered best to keep the ISO as low as possible in order to get the best resolution from one's camera and lens and to avoid "noise" (which is similar to, but not identical to, what in the terminology of the film days, we called "grain").
In one's reading they may run across the term "holy trinity" when applied to lenses, and the major camera manufacturers indeed do each offer their own variation of this. For instance, Sony's previous "holy trinity" consists of the 16-35mm f/2.8 GM, the 24-70mm f/2.8 GM and the 70-200mm f/2.8 GM. However, now Sony is in the midst of revamping this by updating their lenses, so as of now the newest "holy trinity" includes the 12-24mm f/2.8 GM, the 24-70mm f/2.8mm GM and the 70-200mm f/2.8mm GM. The 12-24mm is a new lens released early in 2021, and Sony has just released their new version of the 70-200mm GM, so it's a no-brainer to assume that the 24-70mm GM will be coming along sooner rather than later as well.
From my Nikon days if I recall correctly the "holy trinity" (DSLR lenses) is 14-24mm f/2.8, 24-70mm f/2.8 and 70-200mm f/2.8. Not sure if they've got all of these now covered in their mirrorless line yet or not. I've never used Canon, never bought any of their lenses so am unfamiliar with their offerings but I can guess that they, too, present the same range in a "holy trinity" of zooms.
An advantage of having a "holy trinity" of zoom lenses is, of course, that it covers the entire range from the widest lens in the set to a telephoto. Some people like to have the "holy trinity" and then also build around that with prime lenses. Others find that they don't really need or want some of the focal lengths so skip one or more of the components of the "holy trinity." Some users prefer all prime lenses and so create their own "holy trinity" of those instead.
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