Alicia, I know it posted this a couple days back, but I looked at your profile and you're trying to get work as a virtual assistant but you performed badly on the tests you took relating to your skills as a virtual assistant.
I would suggest you go to your profile and hide those scores and then take any other test that you are certain you can pass (even if it's the spelling test) and display that instead. Then, when you are able to retake the failed tests, be sure you've improved enough to pass them.
If a client looks at your profile and sees that you've failed the VA tests, they aren't going to want to hire you.
Personally, I dislike the tests here and don't think they fairly measure a person's aptitude in their field. But clients don't know that. So hide your bad test scores and then look through all the tests until you find one you're confident about. Take it, if you do above average, display that test instead.
There isn't a magic way to write a proposal to guarantee you'll get the job. Every job is different. Every client is different. You have to tailor your proposal for the specific job for which you're applying. Focus on the client, their problem and how you are going to fix that problem.
Getting the first job is hard. Getting the twentieth job is hard. It gets easier, but not by much. So read the forums, learn as much as you can about Upwork, and you'll do much better. Yes, it takes a lot of time to read the forums, but I promise that it will help you. Read the freelancer forum first (or the New to Upwork forum), then the Clients forum, which will quickly tell you what not to do right from clients. Read all posts in each forum from at least the past six months. That helped me more than anything else did.