Dog pawing at door to get in

It is not realistic to expect a dog to be content isolated in a backyard when just brought into your home last week.  At this stage, the psychological needs are significant and she needs more than anything to bond to you both, and learn that she can trust you.

It is asking a lot to put a lot of breeds outside - my own won't tolerate it either as these are pack animals.  But recognize the unique needs right now having just entered your home. That doesn't even feel like her trusted space yet.

As I do rescue and place dogs, I always require for example that the new adopters take some time off work, pick up the dog at the end of the week etc. to maximize the bonding time they will have.  I also recommend that they spend time with the dog, and in the case of separation anxiety (which your girl may have some) ensure that separation is done very slowly, and very gradually.  In extreme cases for example, it is important that to show the dog what to expect and that you leaving is ok, I have the person walk outside for seconds....wor king up to a minute, then 2 etc.

To get her accustomed to outside, if she is going to need to be out there (remember that no dog should be isolated outside for hours on end) for periods, start introducing it to her in a positive way.  First, spend time out there with her and show her it is a good place.  Then give her a stuffed kong with tasty treats inside to occupy her, and go inside for a brief period.  Work yourself up and gradually increase the time, ensuring she has something to do/eat/work on.  Failure to do these things translates as punishment to her otherwise.

Good luck!