Your question in not so clear, my best guess is that you basically need a "sine oscillator" aka "sine generator".
Searching on wikipedia will help - unveiling amongst others the "Wien-Robinson-Oscillator" and a multitude of other concepts. Some oscillators will do with a single transistor - not even requiring something as "complex" as an OpAmp :)
Dear Sibabratha, truely speaking you cannot get a pure sine wave from electronic circuits. Only they can be as close as possible to a sine wave, but never can be a pure one. You can get a pure sinewave only from rotary machines.
If the frequency has to be variable, the Wien ocillator is probably the best option, the only problem is to stabilize the wave amplitude.
But if you need a fixed frequency sine wave: Connect the op amp as a square wave oscillator: positive feedback and an RC in the negative input. In the capacitor you get a more or less triangular wave. Filter this wave with a 3 step RC filter (each resistor being at least about 4 times higher than the previous one, and the capacitor proportionally lower) and if your filter has the correct value you will get a sine wave with incredible low harmonic content.
If you need a fixed frequency sine wave, search keyword "Band pass filter – comparator oscillator (spot sinus)". That's very good circuit with stable amplitude of oscillations. Or see the book below.
Book Theory of electronic circuits
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