The official installer
How the official Mac version works, and where it stops.
MetaQuotes does publish an installer for the Mac, but it is not a program written for macOS. As its own documentation explains, the installer downloads and configures Wine, a compatibility layer for Windows software, and then installs MetaTrader inside it.
It needs macOS Catalina 10.15.7 or later for MT5 and macOS Big Sur 11 or later for MT4, and it supports every Apple processor. On Apple silicon the Windows code runs through Rosetta 2, Apple’s translator for Intel software.
For manual trading it works, and for many people it is enough. The limits come from having two translation layers between MetaTrader and the Mac, either of which can break with an update.