What does it mean to "simulate a qubit"?

A university student with a background in hardware emulation and computer architecture was challenged by a professor to build a quantum simulator using RISC processors, starting with a 2-qubit system. The project aims to replicate Fujitsu’s 40-qubit quantum simulator, requiring the student to model qubit behavior, including superposition and entanglement, using classical hardware. Key technical hurdles include simulating quantum entanglement, which demands precise mathematical representation of qubit correlations and state evolution via unitary operations. The student seeks guidance on foundational concepts, practical implementation strategies, and scalable architectures for expanding beyond 2 qubits. Recommended next steps include studying quantum gate decompositions, state vector representations, and existing open-source simulators like Qiskit or Cirq for reference.