> I do not know anything with the programming, and to learn I need source code Of a program which manages the external eeprom

You are on a PICBasic forum, and posting in the PicBasicPro section. By that we all assume you have that compiler. If you have the program then you will have the manual (the manual is also freely downloadable from the manufacturers website). In the manual you will find commands I2CREAD and I2CWRITE, once you find those, then the rest is self explanitory.

> but I cannot make the modification.

Then you have a problem, because people here, though willing to help, are unlikely to write your application for you. That requires some effort on your part...