How to run a electrical wire to new building?

If you are not familiar with electricity I would hire someone who does this for as a living. Should be able to find in the yellow pages in your area.

If the ground is rocky or wire is to run under a high traffic area like a driveway I would use teck cable. Teck cable is armoured and has a tough jacket on it making it ideal for rocky ground. If the ground is not rocky for example running under your lawn you can use NMWU cable. This cable isnt armour coated but can be buried in ground. NMWU cable is a lot cheaper to use than TECK cable. If ground is rocky you can also run the NMWU wire in pvc conduit. This way is also a cheaper alternative to using Teck cable. As far as what size wire you will need to use you will need to figure out how many amps will be required in the garage. Hope that helps a bit.

If you have a fuse box, change it out. It needs to be a circuit breaker box. A fuse box is outdated and not as safe. At that time, you can add another breaker or two for your new building. Please, have an electrician do this.

Suggest you start with your city code compliance/building and safety. Most cities require licensed contractors to perform work in certain specialities like electrical, mechanical and gas. An exterior run of wires, fuse box will likely require a permit. There will be guidelines on wire size, for the distance, capacity and connector types. After you have that information you can decide if this is a project you can take on as a diy. Hope this helps.

Thank you everyone