I read about Service endpoint. How does it differ from a BT?
Both show the basic metrics like Load, response and errors.
Have you looked at the documentation on Service Endpoint?
The doc clearly elaborates the distinction:
A business transaction offers a view of application performance that cuts across the environment, reflecting all services that participate in fulfilling the transaction.
Another way of viewing application performance, however, focuses on the performance of a particular service independently of the business transactions that use it. Like business transactions, service endpoints give you key performance indicators, metrics, and snapshots. However, they provide that information exclusively in the context of that service, omitting business transaction context or downstream performance data.
Hope it clarifies your query.
Let us know if you have further questions.