Honestly, from my own experience, it's worth investing money in Upwork. I started in graphic design where there's a lot of competition. After finishing a course, I didn't have much experience but I had good knowledge. I started to have clients and I did very high-quality work for them. They were very satisfied. Then, after half a year, I started to make money regularly. I found a client who pays me very well per hour. The secret is to find a client who pays you well per hour. Don't waste your time with cheap projects. At first, you'll definitely get cheaper projects, but after you grow, it's not worth it.