We want to first welcome you to Upwork! There are many ways to get to 100%, but some items are required. To reach 50% you’ll need a photo, profile overview, at least one employment history item, and at least one skill tag. Any combination of the other choices can then be used to reach 100%. You can find more information in this help article.
Additionally, feel free to check these articles to help you create a profile that stands out and improve your profile title and overview. For some great tips on writing proposals that win jobs, check out this article.