Your TV and aerial need to be connected by coaxial cable for your TV to work. Most properties have wall mounted connection boxes – similar to electrical plugs – that you can simply plug your TV into. If you don’t have a cable, it’s easy to pick up one from most DIY shops.
If you’re installing a new outside aerial, you may be able to reuse the old cable. If you can’t, you’ll need to route a new one down from your aerial to any sockets you need. Coaxial cable can be routed down the exterior of your property, through loft spaces, under floors and along skirting boards.