Does the SLR camera have zoom?

First of all, autofocus and autofocus are not the same concept, so I don't understand what your supplementary question says: "Even if there is no lever, there is no autofocus?" And then what?

In most cases, the zoom of SLR cameras can only be achieved by manually adjusting the lens, which is determined by the structure of the lens. However, a few years ago, companies such as Pentax, Canon and Minolta introduced automatic electric zoom lens, which has a zoom button, can zoom without manual operation, and can achieve explosive effect in the process of taking pictures and exposure. However, this kind of lens has complex structure and high power consumption, so it has hardly been developed since then.

So the lenses of SLR cameras are all manually zoomed, and we can't see the automatic zoom lens anymore.