You can register in the state of your choice within 30 days of purchase. All states issue 30 day temporary registrations, through the dealer or at a courthouse or DMV office in the case of private purchase.
All states I know of permit vehicle registration to foreign nationals with documentation.
Contact the state DMV office for particulars.
Certain states are popular, or simpler in rules or taxes. Since you do not have income in the US, a state without sales tax on vehicles and that permits online renewals such as Oregon may be a choice.
Also consider insurance rates for the various States. While Oregon does mot have a sales tax, in the long term insurance could be much less in another state. Fot that, look at mid American states.
