Embracing new things can be intimidating and downright scary. I remember the first time I heard about the benefits of lifting weights, I was apprehensive. I thought I could just call others 'meatheads' and use my advanced degrees in computer science as a shield. But life does not work like that; we must continuously improve ourselves, in all aspects of our lives: social, personal, physical, intellectual. Learning to buy clothes and put together outfits is just another part of growing up, just like learning how to work out, or how to apply design patterns to a programming project.
On a more practical note, there are tons of resources on the Internet that can help you with figuring out what 'nice' clothes are, or how to put together outfits. Maybe start with this: http://www.kinowear.com/blog/science-of-style-introducing-th... . Or check out reddit's r/malefashionadvice guides, or maybe go on styleforum.net, or try putthison.com . Good luck!