I assume you are talking about a tower crane. You’re correct in the sense that another crane is required but the extension boom of a mobile crane can actually lift the pieces of the crane quite high. The bottom of a tower crane is bolted down to the ground and sections of the frame and slowly added and attached until the desirable height is reached.
There’s a frame just big enough to fit a section of the tower inside it, so you build the first little bit of the tower, put your crane and big frame on top (using a smaller truck-mounted crane), then you jack that frame up high enough that you can fit another section of tower, bolt it all together, and repeat that until you’ve got your crane all built up.
Latest Answers