I have no learn in Flex nor experience using it, but before I
would like to know if there is a need for a Server side program to
be installed, it needs anything to be installed on a server, if
yes, what is it?
There is no server side requirement for creating and
deploying Flex applications if you are accessing your date via web
services http request.
If you need more comprehensive access to server side
resources (java objects etc) then there is an Abobe add on product
(Flex data services) that is a separate license and would require a