The Suit for declaration is to declare a right of the party/plaintiff and when the right is peratining to property , the suti is for declaration title/ownership and also for recovery of possession , if the plaintiff is not in possesion , if the plaintfiff is in possesison suti for delcaration title and Injunction not to interfere with the possession of plaintiff . It all depends on the facts of the case and rights of the party /Plaintiff
When the plaintiff's deceased father is the owner of the property and no legal heirs except the plaintiff and defendant is in possession of the property, then the plaintiff can file a suit for declaration that he is absolute owner of the property and to recover possession of the property from the defendant
In addition to above, every suit shall be filed/instituted by the presentation of a plaint or in such other manner as may be prescribed. Please go through the OrderVII of the Code of Civil Procedure Plant.
Suit can be filed for getting a declaration from the civil court. As a relief the party ask then for possession of the property. The suit can be filed in a court having jurisdiction where the property situate. Please follow the property related suit procedure.