IMO the most dangerous thing you can possibly do is be fit and enter a road race with little to no group riding experience. Wheel to wheel racing is a different beast. You will get chopped, divebombed, brake checked, kickbacked, bumped, squeezed, choked, hooked, and god knows what else.
Find a group of racers. You might suffer a bit on the longer rides for like a couple weeks, but if you're a D1 athlete l, you'll be hammering in no time. Learn to predict people's movements, navigate the pack with no brakes and relax. Once you've done a year of that, then join a race. It would be a tragedy if you crashed in your first race and ended up unable to ride for 3-6 months.
Actually... it's unclear from your post whether you're new to cycling or just new to racing. Regardless, find a friendly practice street race first.
If you haven't already, watch some road race videos. Norcal Cycling aka Jeff Linder has some fantastic videos.