How do I make an HDD as fast as an SSD?
I'm afraid that's impossible. Your hard drive is essentially not much different from an old record turntable: it has spinning disks and a 'head' that writes or reads the magnetic stripe at a point on the wheel.
There are many different mechanical parts that all contribute limitations to the maximum possible speed.
Furthermore: it's a sealed unit, made in a factory. If there was some easy 'tweak' to make it as fast as an SSD, the manufacturers would have done it.