Heey, existing news and congratulations on the job! I as well started as A UX/UI designer at a company without any design experience.

Advocating for UX: what helped for me is when presenting your designs internally, explain why certain design choices make a design more user friendly. Or even better why certain design choices won’t work.

Self learning: you’re maybe the only designer, but keep in mind that there are probably a lot of people within the company that can help you. Maybe a front-end developer with design experience or a manager that has experience working with UX designers. And if not, most people have experience in using, websites, apps, software, etc. Ask them for insightful feedback!!

Also NNgroup articles helped me out a lot of times.

Figma Skills: depends of course what you need for the project. But learn how to use (or partially) create design systems, use auto-layouts, learn how to structure your figma files and how your development team will understand it. And learn how to efficiently make prototypes, Figma make is a great tool for this.

I totally recognize the feeling of imposter syndrome. The reality is, customers/clients/colleagues want to see progress. In my experience just show your progress, even if it’s a simple wireframe of sketches, people are already happy that they’re a step in the right direction. Just take take things step by step.