Hi arkiboys
Reg question #1 - If you have multiple activities in a pipeline, say PL1, and you want to capture errors in each of the activities when they fail, you can use a master pipeline, say PL_Main and call PL1 from PL_Main and then use a stored proc to log errors from PL1 or you can use copy activity to log errors.
SO thread that discusses this and other alternatives-
Here is.a link to implement a stored proc for error logging.
Reg question #2 I believe you are asking about custom alerts., Please take a look at this video or go through this.
Hope it helps. Kindly let us know if you have further questions.