Originally Posted by
Bandera
Join a club, pin on a number and proceed.
Any decent entry level road bike in good mechanical condition will do to see if you enjoy the experience.
Have at it.
-Bandera
This may or may not be a good idea. We know nothing of the OP's group riding experience, and bike handling ability.
The much more responsible approach is to follow the progression set forth in the linked thread.
It's also the progression that's more likely to lead to a positive first racing experience and a desire to return.
Going into your first race, nevr having ridden in a pack, or even worse never having ridden in a pace line, can be a recipe for problems.
So the firs part, join a club is a great idea. Join a club, ride with them for a bit, talk to them, learn from them, and then pin on a number.