Overview
The BCM2711 is an uncategorised made by Broadcom with 431 pins.
PCBKit's library has its footprint (bga-484-440-15x15mm-layout22x22-p0-65mm:BGA-484-440_15x15mm_Layout22x22_P0.65mm, from Antmicro), ready for a KiCad board.
Symbol
The library has no symbol for this part yet.
Footprint
Questions
Is there a KiCad symbol and footprint for the BCM2711?
Yes. the footprint bga-484-440-15x15mm-layout22x22-p0-65mm:BGA-484-440_15x15mm_Layout22x22_P0.65mm, both drawn on this page. PCBKit places them on a board for you when you design with it.
Where is the BCM2711 datasheet?
Broadcom publishes it: the Datasheet link on this page opens it.