You can see jobs pop up in your home page. You need to read the job requirment. If you can do it, then you need to write cover letter or proposal. You will describe your experience. You can come with project plan or outline or with your suggestions to complete the project. Your availability and your price. You will invite to your client to do more discuss on the project. I hope that you will get the project.
The proposal is a combination of your introduction to the client, marketing your skills and experience and providing a solution how you can solve the problem.
If you write the best proposal you will see the result in few days. Though some clients post job and went for sleeping and never came back, in such case, you will see result after one month
As a freelancer, you should know what a proposal is. As a "copywriter", your profile needs a lot of work. And you might want to think about hiding your test results before submitting any proposals.