<p>Blockchain has captured several fields including industries, banks, balloting procedures, medical care, etc. with its innovative technology. The most significant and in-demand of these is healthcare, which uses IoT devices to record patient health conditions and uses EHRs (Electronic Health Records) to store patient's health records. Scalability is one of the significant issues with blockchain networks. It gets slower whenever the number of people or nodes in the network increases. This paper presents a Blockchain-enabled EHR system that stores patients' health records after being categorized through the machine learning model. The decision tree model takes the patient records and sends them to the blockchain, which is divided by the severity of the disease. Lung cancer patient records are taken, and three blockchains are created based on severity i.e., high, medium, and low. The Hyperledger fabric generates and stores the EHRs in the blockchain network. Further, storage capacity and access time are used as performance metrics to assess the proposed model's effectiveness. The system's throughput is also analyzed and compared with the prioritized blockchain system. Our proposed system is expected to assist the medical community in securely storing and prioritizing patient healthcare information. Finally, a comparative study is conducted to show the efficacy of the proposed model.</p>