How to remove all unnecessary text in Notepad++?

Question

Notepad++

Hello.
There is a sample text:
* space * account_nickname number of subscribers
Purpose:
1. remove the space at the beginning, before the nickname.
2. Delete everything that comes after the account_nickname

Then
there is a solid text like:
Nickname#name (written together)
Purpose:
1. Delete everything after #.

And the third request.
Sample text:
First name Last name Middle name
Only the last name should be left, i.e. delete text before and text after.

Tell me, please, how to do this?

Answer 1

Find: ^\h+(\S+)[^\n]+
Replace: $1
Find: #[^\n]+
Replace:
Find: ^\S+\h+(\S+)[^\n]+
Replace:$1