Increasing flap angle reduces lift-off speed but also reduces acceleration rate.
The reduced lift-off speed tends to reduce take-off run.
But the reduced acceleration rate tends to increase take-off run.
If we increase flap angle up to the optimum angle, the dominant factor is the reduced lift-off speed, so the take-off run is reduced.
But if we increase flap angle beyond the optimum angle, the reduced acceleration becomes the dominant factor so the take-off run is increased.
Climb angle is proportional to excess thrust, which is thrust minus drag.
Increasing flap angle increases drag.
So any increase in flap angle decreases excess thrust and decreases climb angle.
So climb angle is maximum when climbing with zero flap.
Putting it all together.
Increasing flap angle up to the optimum value will decrease take-off run and decrease climb angle.
Increasing flap angle beyond the optimum value will increase take-off run and decrease climb angle.