The healthcare sector increasingly relies on digital technologies for storing, accessing, and sharing sensitive medical data, yet challenges such as data privacy, interoperability, security, and trust persist. Traditional centralized systems for managing Electronic Health Records (EHRs) are vulnerable to cyberattacks, unauthorized access, and data fragmentation. Blockchain, with its decentralized, transparent, and tamper-resistant architecture, provides a transformative approach to overcome these limitations. By integrating blockchain with distributed storage and smart contracts, healthcare ecosystems ensure secure data exchange, patient-controlled access, and regulatory compliance while maintaining efficiency. This study highlights the role of blockchain in enhancing EHR management and enabling secure, seamless data sharing among hospitals, laboratories, insurers, and patients. Block chain techniques PoR, PoS, PoTE, PoW, PoCW are used to calculate the EHRs. Among the techniques PoR achieves the highest throughput of 98%. Furthermore, it explores scalability, interoperability, and ethical considerations that influence its adoption. Overall, blockchain holds the potential to create a patient-centric, trustworthy, and resilient healthcare data management framework.