Motor has knocking sound it was out of oil and drove what causes it

So would i have to rebuild the motor or buy another one

I find it to be best to locate a good salvage engine as a replacement. However it needs to be checked out first to confirm engine replacement is necessary. It is possible there is something external causing the “knocking sound” ..

What is external and how do i find out ?

Could a knock sensor have anything to do with it?

Could a knock sensor have anything to do with it?