Its been 25 days i got state tax but still waiting for federeal tax refund.

Only the IRS and your State control when and if a Federal or State tax refund is Approved and Issued.

Once a tax return has been Accepted by the IRS or a State, TurboTax receives no further information concerning the tax return or the status of any tax refund.

If accepted by the IRS use the federal tax refund website to check the refund status - https://www.irs.gov/refunds

After the tax return has been Accepted by the IRS (meaning only that they received the return) it will be in the Processing mode until the tax refund has been Approved and then an Issue Date will be available on the IRS website.
See this IRS website for federal tax refund FAQ's - https://www.irs.gov/refunds/tax-season-refund-frequently-asked-questions