You can self learn Selenium. I know many automation testers who learn selenium on their own by going through Selenium blogs like SoftwareTestingMaterial. Learn Selenium online and practice it until you feel confident. Once you become confident include your automation skills in your resume and if possible showcase your automation skills to your managers. So that you may grab an opportunity in your current organization itself. Before learning Selenium I suggest you learn Manual Testing concepts Java (Core Java is fine). Start with Java and then move on to Selenium.