This widget could not be displayed.

I would recommend renting, or borrowing a tent first before purchasing.  At that point yu will have a much better notion of what will work for you and your dog.  You are probably looking at a three season tent an you don't want it to weigh more than three pounds if you will use it for any amount of backpacking.

Some prefer a two person tent, even if solo ,for the extra room, but that will mean extra weight or a more expensive purchase.

A tent really shines when you encounter rainy,or snowy, weather. A bath tub floor, in which the floor material extend sup the sides of the tent a few inches is a desirable feature.

Beware of really cheap tents.  They are a waste of money.