That depends on how it is reported to you.
On a 1099-R?
On a K-1?
Generally speaking, inherited cash (money) is never taxable.
If you inherit assets, that are sold after the person's death and converted to money (such as stocks, other investments, or a home) then you owe tax on the increase in value (if any) between the date of the person's death and the date of the sale. Such income might be reported on a 1099-S (for a home) or a 1099-B (for a brokerage account).
If the estate earns income that is passed to you, it may be taxable although the principal may not be. Estate income may be reported on a K-1.
If you inherit a tax-privileged account like an IRA, 401(k), pension or annuity, it is probably taxable to you because the contributions were pre-tax (never taxed) so the withdrawal is always taxed, whether it was withdrawn by the original owner or an heir. This kind of income is usually reported on a 1099-R.