Cloud Computing and Blockchain being trending technologies play an increasingly essential role in storage. This storage requires the adaptation of solutions that ensure high data security. Fully homomorphic encryption (FHE) schemes, which allow computations to be performed using encrypted data (without knowing the decryption key), are among the solutions that guarantee the integrity of encrypted data and the confidentiality of stored data. In this article, our contribution based on the Gentry scheme, is a symmetric fully homomorphic encryption scheme composed of four phases. Our contribution offers an in-depth response to the technical difficulties associated with the accumulation of noise during homomorphic operations while preserving the confidentiality and security of encrypted data thanks to the bootstrapping process presented in Gentry’s scheme. This ensures the reliability and precision of the encrypted information. In brief, this article presents a practical implementation of Gentry’s homomorphic encryption scheme, highlighting the different phases of homomorphic security and the technical difficulties associated with implementing these systems in today’s technological environments.