In Smart School Examination when you create exam then you will get option for publish exam (check attached screenshot) so if you enable this option and save it then your exam will be publish and student will be able to attend this published exam, also if you have enabled publish exam status then the Status value in the exam list page will be show with check mark.
To publish Examination result after enter students exam marks you should click on edit exam button and here enable Publish Result option and then save it so your created exam result will be published and visible to students at Exam Result page.
