Can sombody help me with initializing the lcd with pic micro controller 16f84a...

 

What kind of LCD their are many and provide us with the datasheet.

 

If you don't have a manufacturer's part number, the most important piece of information is the controller chip used on your particular LCD.

The most popular controller for 2- and 4-line text displays are the HD44780, of which the KSU0066, ST7036, ST7066U and some others are compatible.
The T6963 is frequently used for monotone LCD graphics displays.
There are certainly others, but these two basic types are very popular with hobbyists.