UK hams often use "Digital Monitor (Promiscuous)" mode to hear everything on a repeater. However, a sophisticated UK codeplug sets up proper so you only hear the talkgroups you subscribe to, reducing radio "clutter."
If you want to hit the ground running, several reliable sources exist. Warning: Always virus-scan any codeplug and verify it matches your firmware version. anytone 868 codeplug uk
A proper UK codeplug has these pre-programmed correctly. UK hams often use "Digital Monitor (Promiscuous)" mode