I want to rectify some mistakes. Is there anyway to reopen those sections (mentioned in the title) and correct something?
Yes, of course. While logged into your profile, visit your dashboard (https://www.teachaway.com/dashboard) and click any of the sections you mentioned to add or edit content. If you've already completed your profile entirely and want to make changes, use your profile icon in the top right hand corner of your screen on both mobile and desktop and select the "Edit Profile Summary" option. From here, you'll be able to make the changes you mentioned.
Hope this helps.
Best of luck in your job search!