Hi,
I am an OPT student working in Minnesota.I am single and no one claim me as a dependent.

Bi weekly pay-2696$
Annual pay-70,096$
Federal state tax-258.44
State tax-126.84

My allowances/exemptions
Federal-2
State-1

Are these correct?

No, that is NOT enough. If you keep the exemptions at TWO, you will owe OVER $4,500. To fix this, submit a NEW W-4 and claim SINGLE status with ZERO allowances to increase your withholding to mitigate what you will owe.

The state withholding should be fine. You will owe about $580 on your Minnesota return.

Plus if you are a nonresident alien (you didn't say whether you were), then you are only allowed to claim 1 exemption anyway.

What NewAcct says is true, but that seemed to be "water under the bridge", so I did not bring that up.