Yes, you can withdraw your money any time from any scheme, except in case of ELSS Tax Saving Schemes. ELSS schemes have a lock-in of 3 years from the date of investment.
There maybe some charges and taxes levied by the Mutual Fund companies and the government respectively in case of redemptions based on the type of Mutual Funds and duration of investment. You can read more about it here. We also show you details about the charges/taxes on the redemption page.