@RobertC55 assuming you did not get an ethernet cable ran when the mains cabling was installed the best method is to buy a powerline networking kit which has two adapters that send data over the mains cable. One plugs into a wall socket near the hub and links by the included ethernet cable tge second unit plugs into a wall socket in the garden room. The kits can be boughtvwith an integrated WiFi access point.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
