I know some of the jobs are not shown in my account but others.
Can I submit proposal manually?
For example, some of the jobs are shown to my friend's account but not mine.
And I want to apply on the jobs which is shown to my friend's account.
So I copied the link of job from my friend and submitted proposal.
Is it legit?
You can submit proposals to jobs that fit your skills and experience. Just make sure that you and your friend are logging in to your individual Upwork accounts and not sharing your account details.
I'm sorry but I think you misunderstood. Your friend can share jobs with you by sharing the job post link. She can copy the link, and paste it on any messaging app you and your friend use.
As a gentle reminder, please know that you are not allowed to login, and/or use another person's account as this is a violation of the Upwork Terms of Service.