I will be studying in Italy for 4 months and my driver's license will expire while I am there. Unable to renew before I left (too early) and my license will change because I am now 21. How do I renew on line in Ohio?
Ohio BMV has a web page with instructions for renewing while temporarily out-of-state. The web page does not give any substantial details, but indicates you may phone them or email them and they will send you a renewal packet.
The web page does not explicitly mention foreign addresses. State agencies may not be willing to mail to foreign addresses, either because they don't want to pay the extra postage, or because postage applied with a postal meter might not be accepted for international mail. If that's a problem, the web page says it can be sent to someone with an Ohio address, and they could pay for the international postage and forward it to you. Hopefully you can clarify that when you contact them to get the packet.