You are welcome to Upwork. The two ways of getting jobs is by application and invitation. You apply for jobs to land one, deliver an awesome service and keep good relationship so your client can hire you for same type of job. These are the two major ways I know of. Learn some proposal writing skills to have a better chance.
Kind regards and goodluck,
Hope you are fine. Try to apply in a small project first like $5 or $10. And always check the client is they are good client or just using upwork as a fun. Sometimes people just post a job and they never come back for check there profile. So always check on right side clients feedback and hiring rate. If hiring rate is up 50% it means client is legit. Always check hiring rate of the client.