If you mean just within Canvas, you can click the three little dots next to an assignment and if the option is still there to "Post Grades" then some or all of them are not posted. If the option is greyed out then they are posted. The little eye is supposed to be an indicator. If it is orange then you have entered grades but students can't see them. If the eye is gone, they are posted and if it is still there but grey then the grades are hidden and the scores were generated by Canvas. I have seen that there is a Canvas bug where the eye is not accurately showing though.
