In general, it cannot boot without a CPU.
Do you have any Q-LED indicators that are lit?
If so, please refer to [Motherboard] ASUS motherboard troubleshooting via Q-LED indicators and follow the steps to troubleshoot.
At the same time, please refer to [Motherboard] Troubleshooting - No Power/No Boot/No Display to troubleshoot problems that cannot be successfully booted,
including trying to clear the CMOS and testing with minimal components, isolating the possible cause.
If there is an inoperable part of the process, please let me know which is it.