I want to put a 100 amp sub panel in my new attached garage. What size wire do I need for a approximate 65 ft run? Also, since the whole house is finished, I will have to come outside and run a conduit along the outside of the house to the garage. What size concuit do I need? Finally, what size circuit breaker do I need at the main? Would I need 100 amp, or a double 50 amp?
Thanks, Jack

Need a two pole 100 amp breaker for a 100 amp feeder and panel.

Can use 3- #3 THHN/THWN copper and 1 # 8 THHN/THWN/ Green copper,

Or,

3- #1 XHHW Aluminum and 1 - #6 XHHW Al in 1/1/4" conduit.

If your running Sch 40 PVC conduit horizontally outdoors, it may need one expansion coupling.

The neutral bar in the subpanel will need to be insulated and not bonded to the metal box, and the equipment ground conducotr will need to connect to a equipment ground bar, for all green and bare grounds, bolted directly to the metal box using machine thread screws.

Thanks for your answer. Would it be easier to use emt rather than pvc? Also, what size conduit for that size wire? Finally, do I need to put a ground wire outside to grounded stakes? If I use emt, that would be connected to the main 200 amp house supply, and would be the ground back to the main.

Which is easier will be up to your abilities and knowledge. You will need rain-tight compression connectors and couplings for EMT. 1-1/4" EMT is the size needed for the conductors I listed.

No, since the garage is attached, no ground rod is needed.

While EMT can be used as an equipment grounding conductor, I highly recommend that you pull the # 8 Cu or #6 Al equipment grounding conductor.

Which is easier will be up to your abilities and knowledge. You will need rain-tight compression connectors and couplings for EMT. 1-1/4" EMT is the size needed for the conductors I listed.

No, since the garage is attached, no ground rod is needed.

While EMT can be used as an equipment grounding conductor, I highly recommend that you pull the # 8 Cu or #6 Al equipment grounding conductor.

Thanks again!
Decided to go with pvc, and will pull wire with ground conductor