Many people self-identify as being an introvert when they are in fact shy and scared of social interactions. Yes introverts can be shy and anxious. But those traits are independent of each other.
I used to be shy and introverted. Now I’m no longer shy but I’m still on the introverted end of the spectrum.
If you are new to improving your social skills you most likely don’t know yourself that well. Because you haven’t had a broad enough range of social experiences.
The best way to find out about yourself is to push past your comfort zone, develop your social skills and gain success in many different ways. Only then will you have enough self-knowledge to know whether you are an introvert or not.