There is no built-in protection for your keystrokes even if you are entering a password. There are malicious programs called keyloggers that can record everything you type on a keyboard. They can also record your screen, mouse clicks and clipboard contents.
Is antivirus security enough?
An antivirus solution is not enough to get the right security for your important passwords. No antivirus is foolproof. There is always a chance to miss some threats.
What about using an ordinary virtual keyboard?
There is no protection in ordinary virtual keyboards. Keyloggers can easily record keystrokes of ordinary virtual keyboards.
Use a secure virtual keyboard along with an antivirus to enter important passwords. A secure virtual keyboard is a virtual keyboard that protects its keystrokes from keyloggers.