Submitted URL marked ‘noindex’

I tried these three steps and inspected url on search console, but issue not resolved, displaying following message.
‘noindex’ detected in ‘robots’ meta tag

SEO best practices state that having pages like the 3 you mentioned “should be” marked as no index. Why would you want them coming up in Search Engine results?

If you really want to change them you’ll need an SEO plugin like Yoast, All In One SEO, etc.

Those pages are always dynamically generated for each individual visitor. So having them being indexed by Google is pointless. If a visitor would show up from nowhere and go straight to /checkout/ then you can’t show them anything meaningful on that page anyway, since their /cart/ is empty…

So: you don’t want Google to index these pages.
The language of Google is a bit weird. I think they should say “Warning” rather than “Error”. But their “error” here means “There seems to be a page, but we’re not allowed to index it.” And your response to that would be: “Totally right, you should not index these, thank you.”