If you added a column to the inventory table, then you (and team Administrators) can delete it by clicking Advanced, and Manage columns.
Click Delete to delete the column.
If the column was not created by you and you are not a team Administrator, you cannot delete columns created by other team members. However, you can make them invisible. Click the Visibility button and hide a specific column by simply clicking on the eye icon. When the eye is crossed the column is not visible to you.