Cache memory is the high speed DRAM which is placed closely to the CPU Register, to compensate for the speed bridge.
Not only 1 level, 2 or 3 levels of Cache operate
CPU generates an address
Look in L1, if not there, look in L2, if not there, look in L3, if not there, go to RAM, if it is not there also, we have. a page fault, go to the Hard disk, not there. dirty page!, write it to the Disk, copy it to the RAM, then copy it to the L3, L2 as well as L1 cache.
A lot of things go parallely, so that we get faster access to the desired word.
This is the beauty of memory hierarchy!