The U.S. federal government has no inheritance tax. So any inheritance of cash are not taxed by the IRS. However you state may have an inheritance tax. If you allow me to have your state I can address that as well.
Your additonal information showed up after I posted my answer.
NJ has an inheritance tax, so you will have to report this income on your state return.
Note: my response assumes your inheritance form the friend is cash, and not a cash equivalent such as an investment account, IRA, or annuity, etc.