IF I rent a room and my home is a one family dwelling how am I protected legally if she/he becomes injured while living there?

First of all, you might want to clarify whether your insurer excludes coverage for your tenant's personal belongings, or your liability for any injuries your tenants sustain within the covered home. Property and liability are separate coverage parts and may be subject to different exclusions.

If it turns out only that your tenant's belongings are not covered, you should advise them to purchase a renter's insurance policy.

If, however, you do have an exclusion of coverage for liability to tenants in your homeowner's policy, you might want to inquire with you insurer or agent about purchasing an endorsement to cover a tenant, or other similar insurance product.

In either case, make sure that the rental is "legal" as per your local municipality and any state regulations. Leasing an illegal apartment in New Jersey carries stiff penalties.