If your refund as already been sent, you would have to check your bank to see if there is a pending deposit. If you don't have a date that your refund was sent you would have to check the IRS (& State) websites for information.
You can check the IRS website Where's My Refund for your Federal information?
https://www.irs.gov/refunds
If you have a State refund, click on the following link, then click on your State
https://ttlc.intuit.com/community/refund-status/help