If you don't already have a cable tV connector outside than I would get a coax wall plate and mount it convenately outside on the gray bottom sheet metal after drilling an oversized hole for the barrel connector. You can add rubber grommets to slow evential water damage or maybe use an outside plastic flip open cover over a two port mounting receptacle or maybe a winguart 1024 single coax receptacle.
Drill a hole where you want to come in. Like under the bed/couch anywhere you are sure you want to enter in either under a cabinet so you can hide the hole or it makes mechanical sense but no matter which way you drill look out for wires or water tubes, tanks or the metal frame. Look where you are on both sides use a common inside outside mark like an edge or pipe something that already passes through so you have at least some idea where the hole will come out on the other side. 3/8" is the size for RG 6 coax. Drill a pilot hole first. They you will want to come somewhere convenient if your in a cabinet so you will need to drill a second hole. You don't need a second inside wall plate unless you want one. You may want to use wire ties where the cable is hidden and plastic clamps where it isn't.
I use a Onn 4K Hd Motorized Outdoor TV Antenna With 150-Mile Range I have the incoming cable come to the box so I can control it when the trailer door is open with the remote control pointed at the controller box. The TV is then connected from the antenna control box. I have 39 inch siting in front of the front window. Tvs are measured on the screens diagonal line remember not to forget that the edge and feet need space also.
I have the antenna mounted on a piece of steel EMT pipe and held against the spare tire mount at the back of the trailer with large pipe clamps. The pipe, antennae and outdoor cable disable and the pipe goes into the trailer on the road while the clamps remain outside on the spa.
Coax Cable Crimper, Coaxial Compression Tool Kit Wire Stripper with F RG6 RG59 Connectors
At amazon That looks like a good deal to make professional cables like the cable guy. Use RG 6 tri shield cable four shield is better but harder to work with.
