https://ark.intel.com/content/www/u...5-9600-processor-9m-cache-up-to-4-60-ghz.html
Your turbo boost is 4.6 GHz...
Only when one core is used you can reach 4.6GHz...
Your CPU is Power limited ( TDP... thermal design power), when only one core is being used (usually during normal windows operation) you can boost to 4.6GHz, when more cores are used the clock speed goes down, because its sending more power to other cores.
Simply put you cannot decide when what clock speed is being used.
The CPU that can be clocked/under-clocked by users are with "K" in the end... meaning Unlocked, but for that you need motherboard with Z chipset as well.