You absolutely can upload your resume to your career center account. Click on the Manage Resumes tab under the Job Seeker drop down menu to navigate to your resume page. You should see a button towards the bottom of the page that says "Upload Resume File." Click on this button to upload your resume to your account.
You may also choose the option to Build Resume Online (manually create your resume) or import your LinkedIn profile.*
*You will be required to sign in to your LinkedIn account. Please note LinkedIn does not have exactly the same fields as the career center, so you will have to review the imported information and update where necessary.