Well that's 1/2 of 1/4th (1/8th) the questions I've asked.
My recommendation for you is to take the components to a PC shop and let them get it up and running. Here I cannot 'see' or 'guess' what components you have to begin to help you.
You can try booting with (1) one stick of RAM, failure swap out the other (1) stick of RAM.
CPU: | -- | RAM | -- | -- |