Welcome to BuddyPress! I’m sorry it has taken this long to answer your question.
First let me answer this question:
do i need to edit the bp-core component and bp-xprofile too?
You should not edit any of the core BuddyPress components as your changes will be lost the next time you update BP. Instead, you can either take advantage of the bp-custom.php file (detailed here), or create your own custom component.
can someone expalin me the use of bp-xprofile component.
Here’s some information on BuddyPress’ profile features that may help answer this question.
also, i want to create my own component
There is a specially-created tool for this called the BuddyPress Skeleton Component for plugin developers. Using this series of files, you can create your own custom BP component. There is a download link on that page.