Engine was running fine, sudden mass of white smoke and RAW oil out of exhaust. Found rubber tube from block to carb. Inlet had come off.
Re-connect tube,replaced spark plug. Getting fire but has weak compression.
Does not appear to be getting gas. Exhaust will get WARM while cranking but will not start (does not make an attempt). Broken ring or stuck valve?

Could be rings. Have you done a compression, or leak down test?

Sounds like you need a new engine