Fresh Manual Install
Make sure you upload contents of wordpress folder in root public_html or httpdocs if you installing in root or if you installing in folder then upload wordpress folder as is in your root and you can rename the folder to your liking.
If you are installing WordPress manually for first time and you get a 500 server error or blank white page then you will need to check the permissions of your root folder as in most linux cpanel server public_html or httpdocs needs to be 750.
Next check if all wordpress folders are 755 and wp- files are 644.
If you still have problem opening your install program then Internal server errors are usually described in more detail in the server error log. If you have access to your server error log, generate the error again, note the date and time, then immediately check your server error log for any errors that occurred during that time period. If you don’t have access to your server error log, ask your hosting provider to look for you.
Once you know the file that is causing the problem you can replace the file or folder with a same file from your wordpress download and then try install program.
If you edited wp-config.php prior to upload of files and folders delete the file and keep wp-config-sample.php file and let the install program walk you through creating the wp-config.php file. Make sure have your database name,database username,password and DB_host handy and copied. (In Cpanel the names are prefixed cpanelusername_)
Some host use a some sort of url instead of default localhost for DB_Host so check with your host if you are not sure what to use.
If you getting a blank white screen then I have a article that will help you on causes of a blank white screen.
Discover how you can blog like othe successfull bloggers with simple step by step Techniques.