Using a microphone/computer/AV receiver together

by Paul
(Charleston, SC)

Hello,

My name is Paul. I am currently trying to set up a system for my sister's wedding that allows me to plug a sony dynamic microphone into my laptop computer, which is plugged into a sony AV receiver and 4 speakers. The primary use of this system is to play music, but we are planning on using the microphone for announcements and some brief speeches. The set-up is working perfectly, and I am having no issues except that I am having trouble finding a program that allows me to speak in real-time, not record my voice. Is there a program that can be used for this type of application?