Please click on your photo in the upper-right corner > go to Settings > scroll down and click on the Create a new account link. Proceed with creating a freelancer profile which is used to offer services, unlike the client profile you have now, designed for hiring other freelancers.
Your profile will need to be approved before you can start actively using Upwork.
Could you please clarify something for us?
Are you a new client and you want to create a job posting and hire a freelancer to,work for you?
If the answer is "yes," then we need to provide you with different instructions.
If you want to work as a freelancer, then I can see that Vladimir has provided helpful instructions about what to do next.