I have been working on Upwork's platform for so long and I can say honestly is far the BEST place where you can find great projects to work with. Also you can build a business profile that have a huge impact in your career.
The contractors are great, not scammers as other freelancers website, everything is super secure to work, receive in the right time.
Once you get experience on how using the website, how send proposals, how to decide whether is good or bad projecto to work with, the better will be the experience.
You can easily flag bad job offers, which helps the platform to remove bad contractors or just wasters of time and energy.
Love Upwork!
Thanks