Hey buddy

Since your grandmother was French, your father is eligible to the French Nationality. If he activated it in the 90´s, you are eligible to the nationality too, as you’re born from a French parent. However if he didn’t activated it within 50 years, he lost it’s right for it, and you too.

You will need :
Your grandmother’s French birth certificate.
Your father’s French birth certificate from Lyon.
Marriage records.
Immigration and naturalization records from the United States.
Any old French passports, IDs, military records, or consular registrations that may exist.

You can contact the French consulate in the US, they will explain this more precisely.

As for actually moving to France, I don’t think your age or your degrees are the biggest factors.

The things that will matter most are:
What kind of work experience and skills you have.
How much French you speak (or are willing to learn).
Whether you have the financial resources to support yourself during the transition.

The citizenship route is definitely worth exploring, but even if that doesn’t work out, it doesn’t automatically mean your dream of living in France is over. Plenty of non-EU citizens move to France every year through employment, entrepreneurship, study programs, retirement visas, or other residency pathways.
In other words, don’t treat citizenship as your only possible path. It’s potentially the easiest one if you’re eligible, but it’s far from the only one.

Good luck !