how can i add the repeater field in buddy press user edit profile

You can try using BuddyPress Profile Pro plugin. It allows you to add repeater fields and groups pretty easily. Follow these steps:

1. Download and install the plugin.
2. Now, you have to create a repeater group. Head to Group Setting
   tab.
3. Enter Group Title and Group Description. Check the boxes for
   the options Display Group at Buddypress Profile and
   Repeater.
4. Click on Add button.
5. Now, you have to add fields inside groups. Head to Field Setting
   tab. Enter Field Title, Field Type and Field Group.
   Check the boxes for the options Display and Required.
6. Finally, click on Add button.