Although installation normally goes easily, there are sometimes issues due something missed in the installation process or differences in servers. Here are the most common.
You did not change the constant "siteURL" or else did not clear the cache after you did so. See #12 above.
First check the constant "siteURL" (see #12 above). I f that is OK then make sure you have the hidden file ".htaccess" in the root of the site. If not the rename the file "_ copy_of_.htaccess_original_is_hidden" to ".htaccess"
If all else fails, comment out the RealURL code in the Base TypoScript Template in the back end. After clearing the cache, the site should run using URLs like mysite.com/index.php?id=12. If it does then it is something with your server configuration and RealURL
Check the ImageMagick settings in the install tool. The path may be wrong or you server may be set up for GraphicsMagick. In any case the install tool is where you should look.
Here are some additional resources on how to install TYPO3 sites.
These are the username and passwords you will need.
TYPO3 Install Tool
After installation, change these passwords and when finished with the install tool, delete the file "ENABLE_INSTALL_TOOL" for more security.
Historically I have used U.S. date formats (mm-dd-yyyy) in the QuickSite, but now with its use by the general TYPO3 community its makes sense to change that to the TYPO3 default (dd-mm-yyyy). Therefore I have eliminated the following line from localconf.
$TYPO3_CONF_VARS['SYS']['USdateFormat'] = '1';
You can change this back to U.S. date format in the Install Tool.