I have few question related to Website Security.
I have a lot of website but i have few problems related to website security.
How i can protect my website from viruses etc.
My website upload using FTP.
There is no virus but i fear that is it possible in future, so i want to prevent this thing. 
You should enable suPHP and suhosin that will protect your sites from various php vulnerable codes to be executed on the server. Also, it is always recommend to have third party firewall like csf or apf installed on the server. Also, you can disable few php function to be executed on the server like exec () etc etc which could cause to get access to your php codes. There are many aspects can be considered in order to secure your server which is not limited to. 