How to find the right DLLs?

Question

C++ / C#

How to find the necessary dll for a specific task?
So I need a dlkku for convenient work with http requests, and then another one for working with tables, and then another and another, but how to find it?

Answer 1

And what does the dll have to do with it?
Everything is already in the seasharp, read msdn

Answer 2

to work with http requests
https://msdn.microsoft.com/ru-ru/library/system.ne...
https://msdn.microsoft.com/ru-ru/library/456dfw4f(...
https: //msdn.microsoft.com/ru-ru/library/system.ne...
for tables look for Excel Interop