Views can only be created and modified in Classic SharePoint. (Take a look at this article to learn the difference: Classic SharePoint and Modern SharePoint.)
If you are in Modern SP, you can switch to Classic. (You'll know you're in Modern if this link is in the lower left corner of your screen "Return to classic SharePoint".)
Create a View
If you are in a library, click the Library tab in the upper left corner. If you are in a list, click the List tab in the upper left corner.
- Click Create View
- Choose Standard
- Name the View
- Select Private or Public View
- Select the columns and order them as you want to see them
- Click OK
Select a View you Created
When you go back to the Library or List, there are 3 ways to select the view:
- Under the link to create a new document or new item
- From the Library or List tab, click the drop down under Current View
- From Modern SharePoint, on the right side of the menu bar