Most VGA monitors won't support the CPCs signal directly and require an [[LCD_monitor_and_LCD_TV_Solution_(RGB)#Converter_options|active converter/scan doubler]] but some monitors are accepting a 15.6kHz signal like provided by the CPC.
In the late 80s and 90s there were a couple of CRT multisync monitors like the NEC Multisync series. For modern LCD monitors the support of 15.6kHz is rare but there are a couple of monitors that are known to work well: httphttps://15khz.wikidotmiraheze.comorg/wiki/Main_Page
If you own such a monitor you can easily connect the VGA monitor to the CPC. For most of them, all you need is to connect 5 pins of the CPCs 6pin DIN connector to the right pins of a VGA connector - and that's it.