wall chasing

I'd like to install some recessed brick lights in my wall in the rendered section under the cedar - see photo. As far as I know it's a cavity block wall. Wondering how easy or difficult it would be to cut out the recess for the light - and wire up from ground level. Presume I'd have to get the...

don’t really know any sparks so hopefully i can get some advice please. I’ve just bought a house and all the sockets aren’t sunk into the wall and the cable is the same all ran in pvc trunking around the whole house. Looks like there’s been a rewire as mostly new cable’s but i want to chase them...