|See the cable that goes from the wall to the router?|
You can buy as long a cord premade as you want to string from places like Lowes and Home Depo or Staples.
Closer you can get your wireless router to a window or a wall next to a window [some windows insulating gas componets block wifi] in site of the garage and have him move closer to the house the better chance of a good signal you have.
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