Your site http://extremetodownloads.com/ is working fine for me.
Generally When you change the DNS entries, It may take upto 48 hours for DNS to propagate.
Clear browser cache, Flush DNS and try to access site again.
.htaccess file can be found in public_html folder, It is hidden file.
While opening file manager, make sure to tick "Show hidden files and folders."
Then you are able to see the .htaccess.
I thought the why question is for index of / page, I just explained why it shows as it doesn't have any default files to load with the name index so it shows the files list with the name index of / . :)
If you want to reset it back then there is no automated way than terminating the account by requesting and creating new one.
Otherwise you can delete the all the files and folders inside the public_html folder(NOT public_html) It is same as new....
Read about High Resource Usage
For the first two times you can unsuspend yourself and after the third time you have to post a request a thread here in forum then we will unsuspend you....
After the third time once we unsuspend you we may give you the information to resolve the issue which...
The folders like Administrators, Editors etc... are giving the Internal server error
Check the File Permissions in all the sub folders
For files they should be 644 and For folders 755
giving 666 or 777 may lead to Internal server error....