The top command in Linux displays information about the processes running on a system, including the CPU utilization. If top is showing two CPUs when you only have one physical processor, it is likely because your processor supports hyper-threading.
Hyper-threading is a technology that allows a single physical processor to appear as two logical processors to the operating system. Each logical processor has its own processing resources and can execute instructions independently. This can improve the performance of certain types of workloads by allowing the processor to perform more tasks in parallel.
If your processor supports hyper-threading and it is enabled in the BIOS, top will show two CPUs even though you only have one physical processor. You can verify that your processor supports hyper-threading by checking the documentation for your processor or by looking for the "HT" or "Hyper-Threading" feature in the CPU's specifications.