That piece of porcelain sucks up all the heat from your water. Invest in a cheap plastic V60. They cost just a few euros.
Get some decent paper filters for it. I would recommend Cafec ABACA (not the plus version!) but the Hario filters work fine as well.
Ideally you want to pour from a temperature controlled gooseneck kettle. That allows you to precisely control your pouring speed. They don’t have to be expensive. Alternatively you can get a Hario Drip Kettle Air for pouring.
And most importantly buy good coffee.