Having serious computer issiues. Need serious help

Hello, I have an old computer that i am currently trying to repair but i have hit a massive brick wall nothing works im getting no video output and when i started it the first time from getting it out of storage it started for a second the something went crack/pop and then some sort of liquid was squirted out of the computer it hit me cause i had the side of the case off. it smelt like electrical burning. now i have the motherboard sitting on my table with only one fan and one hard drive connected and getting no video out of it. the monitor recognises that its been plugged in the just goes into power saving mode what the hell do i do need serious help