Where are you going to shoot? How much distance?
Plinking? shooting at paper targets? Hunting?
At the 100 yard range at my club I see some women (men too including me) who really enjoy shooting the .17 HMR, and the .22 magnum. They have virtually no recoil and make good target rounds. .17 HMR could do 300 yards even.
Next would be .223 since its accurate, and inexpensive to shoot. It has more recoil than the rimfire rounds.
Folks even compete in highpower out to 600 yards with it. If you are looking for a carbine, an m4 clone would be a good choice with a 6 position adjustable stock. Ars are very accurate and fun to shoot.
I have also seen a couple of petite young women shooting the 8mm Mauser, and the 7mm rem mag. preparing to go hunting in one case and plinking with her boyfriend in another.
The WWII surplus Mauser had a steel buttplate
I dont even like to shoot those, but this young lady was smart and was wearing a PAST magnum recoil pad, on her shoulder. I think she went through 3 boxes 60 rounds, and then she traded off for the 30-.06 garrand with her boyfriend and shot it some more.
Women can handle the recoil, if they are taught how. most important is that you get her a PAST recoil shield and teach her how to hold the rifle tightly to her shoulder so her whole body moves with the rifles recoil, rather than it wacking her hard.