Hi,
I will try to put it in a nutshell 😉
Let's say that the Power BI Service is an online version of the Power BI Desktop (not exactly but we try to make the big lines).
It's made for sharing the reports with others (allowing some people with some rights) and it's probably what you call the "reading view". If your company is using the Microsoft service, you can open your Power BI Service at this address : https://app.powerbi.com/
Once on this page you can connect using your Microsoft account and you will see the reports that you have published and the reports shared with you (if any).
If your company is using it's own server for publishing Power BI reports, then you should ask your IT dpt.
Even if we can find exception to that, let's say that you create your reports using the Power BI Desktop and when they are ready you publish them on the PBI Service to share them with others.
And to answer your question, someone who wants a "preview" of its report can publish it to "My Workspace" to see it online without any sharing (unless you shared your personnal Workspace).
Hope it will help you and I recommend some articles for you, like :
https://learn.microsoft.com/en-us/power-bi/fundamentals/power-bi-service-overview
Hope it helps
