Totally understand what you mean. I was scared to ask 'stupid' questions, scared to look like a total newb.
Well, I swallowed hard and asked! I rode! I fell down! And then I didn't. I was embarrassed but I got over it and so will you. No one pointed. No one laughed. Now, after all this time I've ridden in many diverse groups and they all (except the elitist idiots who aren't worth anyone's time anyways) never laughed at someone new. Many are happy to offer advice and help out. It's good to see another person on a bike and we all had to learn.
Do it. Don't let a little worry over getting started stop you before you even step foot on the bike. If you go clipless adjust them so they are very easy to get out of and practice somewhere soft first. Try not to be afraid to ask questions and learning some basic maintenance on your bike will make you feel empowered. Being able to change a flat is a good feeling. (and then get some tire liners so you aren't as likely to have to).
You can do it you can do it you can do it you can do it........it's not about what you wear (except the helmet) or what you ride, it's about enjoying yourself. Last I checked recreational riding's not a talent or a fashion show.
I used to have an open mind but my brains kept falling out.