Do you have to quarantine?

Please do follow all of the information that Mary provided. While there is a chance that quarantine requirements will have changed by October, I would not count on it, especially given epidemiologists' predictions for the fall and winter. That said, you could theoretically make refundable travel arrangements, i.e. a hotel with a free cancellation policy, or flights on Southwest (probably into Boston) which can be credited back to you for use within the year after booking, in the off chance that restrictions are loosened by October.
Personally, I would try to think of this as an opportunity to do more research on the area and plan a potential trip for next year. Vermont and Rhode Island offer very different experiences. If you're interested in seeing fall foliage, most people would prefer Vermont, New Hampshire, Maine, or western Massachusetts, given the prevalance of hardwood forests and the rolling hills and mountains that showcase the colors. Rhode Island is no slouch when it comes to autumn foliage, either, but the timing of your trip will make a big difference in terms of which state to focus on. Vermont and the other northern New England states tend to reach peak colors during the first half of October, whereas Rhode Island and southern New England will showcase their best colors during the second half of the month. You might want to start researching and planning an itinerary that lets you explore the entire region at a time when travel is safer.

> I'm 65, in good shape and use to doing a lot of traveling which of course have not been able to go anywhere this year.
Few of us have been able to go anywhere this year, even those of us who are used to travelling.
When it comes to Covid and quarantine requirements, your age and health status are entirely irrelevant. Being 65 and in good health will not prevent you catching Covid nor, imo far worse, will it stop you infecting others whilst you're asymptomatic. 
Both states require you to quarantine.
Vermont:
>If you plan to travel to Vermont by public transportation (plane, train, bus) or from further than a direct car ride, you must quarantine in Vermont. You may complete either a 14-day quarantine or a 7-day quarantine followed by a negative PCR test, in a Vermont lodging establishment or with friends and family. You must stay in your quarantine location for the duration of quarantine other than to travel to and from a test site.
https://www.healthvermont.gov/response/coronavirus-covid-19/traveling-vermont
Rhode Island requires travellers from Alabama (and other states) to quarantine for 14 days. There is an alternative:
>As an exception, you may provide proof of a negative test for COVID-19 that was taken within 72 hours before arriving in Rhode Island.  
Rhode Island also requires >out-of-state visitors to complete this certificate of compliance with out-of-state travel quarantine/testing requirements and out-of-state travel screening form upon arriving in Rhode Island. Travelers will be required to provide their completed certificate of compliance to their lodging and accommodations upon check-in.  <
https://health.ri.gov/covid/travel/
Neither seem like a 'hit and miss' to me: both states have made it very clear what their rules are. Imo, trying to ignore or avoid those rules would be selfish in the extreme.
Frankly, you....like the rest of us whose travel plans have, for the moment, been put on hold......would do better to either travel to a state which doesn't require you to quarantine or just accept that travelling out of state is simply not a good idea at the moment.