My commode has been leaking really bad and I has a seeping sound coming from it when it is flushed. Also, it will not flush anything well. What could be the problem?

Where is it leaking? Could be a bad flapper valve, or fill valve, or plugged up rim holes and or jet hole.

If it is leaking out from the bottom of where the bowl meets the floor, then you may have a clogged toilet drain, and a bad wax ring.(clogged drain probably blew out wax ring if this is the case). Please give us some more details and we will try to help you out.