Apple does not host a public, standalone "Boot Camp 6.1" executable installer on its website downloads page. Instead, Apple packages Boot Camp support software specifically for your exact Mac model.
refers to the software and driver package released around 2016-2017, primarily supporting Windows 10 on Macs from that era (e.g., 2015–2017 MacBook Pros, iMacs, and MacBooks). However, many users have successfully repurposed these drivers for Windows 11 on older Macs. bootcamp 61 download windows 11 link