If this is sharing living expenses towards your bills, you do not need to report this as income.
If this is actual rent as a discounted rate versus shared living expenses then you would need to include this as income on line 8 Schedule 1 of your form 1040. You would do this by reporting the income under less common income by selecting the following:
Federal
Income and Expenses
Scroll down to Less Common Income and click Show More
Start next to Miscellaneous Income
Start next to Other Reportable Income
You will not be able to include any rental expenses if this is not reported as other reportable income.
What differentiates this reply from reporting the income as described in "I have rental property that is rented by a familty member at a discount to fair market value. Where do I report this income?" (
Intent. If it is paid with the intention of being rental income, then it is reportable income as stated by Diane in that post. If it is paying the persons share of the costs of living with you, then it is considered shared living expenses.