Should this diet/fitness plan get me toned? Please help :)?

Okay I'm a teenage girl 5'1 and 61 kg I really want to tone up I've already started healthy eating so does this plan sound okay
I'll do it twice a day
- 3 reps of 25 squats holding a 3kg dumbell
- 3 reps of weights ( 3kg dumbells raising in the air not sure what that's actually called)
- 3 reps of 100 sit ups (taking a 5 second break after 25)
Then I also walk to and from school
Would I tone up from doing these? Any advice is welcome!
Also for breakfast I have a bowl of whole grain cereal it's like oat clusters with macadamia and honey with a glass of orange juice... Does that sound okay?
Thanks in advance :)