I forgot to mention: there are different "value" treats to use when training. Since you said she is not too interested, you may need to start with high value treats to get her to pay attention since she is young. High value would be what she finds irresistible. (Short sessions and small pieces of treats at first, end on a happy good note and lots of praises. Training should be fun for both of you.) Once you establish a behavior, you can lower the value of the treat and even use her own food if she likes it (that would be a low value treat). You can keep different value treats with you and reward accordingly when she advances. You will be like a slot machine - she never knows what she is going to get. Some dogs are motivated by toys and others by attention, so use what you feel your dog is most motivated to, it doesn't have to be food only but a high value treat is usually the ultimate for most dogs.At first, once you find her high value treat, stick to it until the behavior is well established before giving a lesser value treat. Hope this helps. Don't try to teach complicated things at first, start with things a puppy does naturally; sits, paws you for food or play, lays down, then go from there. Each behavior your dog naturally displays is a teachable "trick". Like bark:click:treat:quiet:click:treat: (do this later on, once she learns more basic commands and learns to "learn"). I had a dog that knew how many times to bark based on my hand gesture; the neighbor kids thought the dog really knew math.
Dogs are visual first so use a hand command and be consistent, always use the same command and word for the behavior you want so you don't confuse her. I will chime back if I think of something else. Best wishes and happy training to you and Stella.