When you get a new DSLR camera body, you typically want a general-purpose "walk around" lens. These are usually "standard zoom" lenses that have a zoom range running from moderately wide-angle (not extreme) to moderately telephoto (also usually not extreme.)
These make very good lenses to get started because they can be used in a broad variety of shooting situations. The lenses aren't optimized to any one kind of photography and there are often better lenses for specific niches within photography. These general-purpose zooms aren't meant to addresses niches.
Canon's "L" series ("Luxury" lenses) are their top-end lenses. The typically have the best optics... but it's far more than that. They also usually have better focus motors, better aperture mechanisms that provide for a well-rounded aperture and smoother out-of-focus blur. They are often (but not always) weather-sealed lenses (weather sealed lenses are not water proof. Do not submerge them. They can handle "spray", rain, etc. but cannot handle water under force or pressure. If you're standing in the ocean and you get swamped by a wave, you've probably damaged the lens and camera.) The build quality is usually significantly better and they can take a bit of a beating and still be fine (they can certainly take more abuse than a typical lens.)
Most L series lenses have price tags that are north of $1000 USD -- though there are a few exceptions.
Canon does make the EF 24-70mm f/2.8L USM II -- and though it's range is only 24-70 and not 24-105, it delivers a more impressive image and it can provide an f/2.8 focal ratio throughout the entire range. It is a very impressive lens, but it's also about $1800.
For farther focal length needs, the EF 70-200mm f/2.8L IS USM II is pretty much impossible to beat. It provides 4 stops of image stabilization, very fast focusing, tack-sharp optics, an f/2.8 focal length throughout the range, and has minimal "breathing" (virtually all competitors lenses have a huge "breathing" issue.) "Breathing" refers to the notion that at any given focal length, if you adjust ONLY the focus on the lens, you'll notice the focal length of the lens is changing (the area that fits within the frame is expanding) so you're not really getting the focal length that you've selected. It happens because shifting the focusing elements within the lens has an effect not just on the focus distance (as you'd expect) but also on the entire focal length (which you might not expect.) The Canon 70-200's have very little "breathing" meaning that you actually are getting the focal length you selected ... or at least very close to the focal length you selected (every lens breathes at least a tiny amount.)
The Canon EF 70-200mm f/2.8L IS USM II is probably the best 70-200 in the industry... but it's price tag is about $2k.
All of this is to say: If you want the very best... you could get the Canon EF 24-70 f/2.8L USM II and the Canon 70-200mm f/2.8L IS USM II and you'd own two very impressive lenses. Also you'd be about $3800 poorer and you wouldn't own a macro lens.
Picking that first lens is a bit of a decision. My general advice in the past has been: If you *can* afford to get both the 24-70 and the 70-200 f/2.8 combination, then that's certainly the highest quality option there is. But if you can't afford to get BOTH of them... then the 24-105 will offer a little more general purpose versatility than you'd get with the 24-70 f/2.8 alone.
If you want a low-light lens option, then the EF 50mm f/1.8 STM (and make SURE it's the "STM" version and not the old EF 50mm f/1.8 II) which is a very low cost way to get a low focal ratio lens. There's also the EF 50mm f/1.4 USM (about $350). The Sigma 50mm f/1.4 Art lens is about $950 and it's better, but of course it's also about $600 more. I do NOT recommend the Canon EF 50mm f/1.2L USM casually... that lens is slow to focus and is NOT intended for fast candid shooting situations (it's really intended for situations where the photographer has time to take the exposure and the ability to control the shot.... e.g. studio situations, etc.) The image quality of the 50mm f/1.2L is better... it's background blur is gorgeous. But it's more difficult to use that lens and if you use it in a hurry then you will not likely be happy with the results.
I think the EF 24-105mm f/4L IS USM an excellent choice for the "if I could only pick one lens... what would it be?" situation.
The EF 24-105mm f/4L does have a "macro" range but it's not a true macro lens. A true macro lens can get 1:1 image scale on the sensor (meaning objects are as large on your 35mm x 24mm image sensor as they are in in real life. If you take a photo of a US quarter (24.26mm) with a true macro lens at closest focusing distance, then the image of that quarter on your camera sensor will completely fill the vertical (narrow) direction of the sensor and will just barely be cropped at the edges. You can imagine that once you bring the image into a computer and view it on the screen that you'd have an enormous image of a quarter.
The EF 24-105mm f/4L IS USM is a 1:4 macro scale. That means the image projected on the sensor is actually only 1/4 of the size of the object in real life (the tightest possible cropping would be roughly the size of four quarters laid edge-to-edge in the vertical direction.)
If you're shooting plants, flowers, etc. then that 1:4 is probably close enough. If you're shooting tiny insects... then you might prefer a true dedicated macro lens.