I sign up for the 30 day trial and I am trying to find the settings > solution > all solution page to create a entity, but cant.
Actually, I did find the page but I don't know how to get back to it - any help is appreciate it on where I have to click.
Have a look below reference-
You might be in the unified interface.
You can access the solutions by using the following url:
Also, in system settings you can choose options for Use the new Unified Interface Only or Show legacy Dynamics 365 app - legacy only.
Hope this helps.
As others suggested, you are in the Unified Interface, and you can switch back to the classic web interface by Settings > Advanced settings > General Tab, and then scroll down to the section titled: Select "Use the new Unified Interface Only” option and set it to "No".
After that, you can navigate in the classic interface.
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