I'm also working as Freelancer, and what I do?
I've solve complex problems on your computer. Troubleshoot the issue and find the root cause. For example you are trying to launch SQL server and recieve error? I can fix it.
I do pentest for Web Applicaitons & Network. I follow the OWASP standards and provide professional pentesting reports.
I write Python & Golang codes to automate some stuff. Especially, I write scrapers, parsers and REST API with Golang.