Any of those help You need to setup a SDK for Java projects, like @rizzletang said, but you don't need to create a new project, you can do it from the Welcome screen. On the bottom right, select Configure > Project Defaults > Project Structure:
No Next and Previous button while importing project in Intellij after intellij Idea 2019.2 update
I hope this helps . As per the following link, it was a regression bug. https://youtrack.jetbrains.com/issue/IDEA-222331 Now it has been fixed. I am using Intellij Idea Ultimate Version 2019.3.2. Find below the attached screen shot below. I have redacted the licensed portion with black color. I hope that this bug may not be there in Community edition.
IntellIj 2018.3 java.lang.AssertionError when refresh gradle project