No I am not saying that. Certainly St. Paul is not saying that: "neither he that planteth is any thing, nor he that watereth; but God that giveth the increase." Since you ask, Jesus laid the foundation for the Purgatory by His death and Resurrection on the cross. St. Paul speaks of the foundation of the faith in Christ that he provided by his priesthood.
St. Paul was a priest? Are all priests given the authority by God to lay foundations? Which foundation did Peter lay? Was it the same as Paul? But wait, it couldn’t have been. Because Paul said HE was given this foundation of grace to lay. He did NOT say he was building on any foundation that God have given Peter to lay. It was different. Both built on Jesus Christ. But Paul said he was a masterbuilder. He did not say he was contracting with Peter. Don’t you find that interesting?