first, take control of any infantryman of your choice. find an enemy tank/armored vehicle (preferrably light/medium tanks or armor) and get rid of their armor with grenades, sticky bombs, or support from artillery or something (they probably gonna try to light you up so keep moving and jumping if you don't want to get turned into swiss cheese)
then when they're unable to shoot just pull out the pistol and blast the HP away! of course you dont have to use the pistol but it's funnier that way
then all you have to do is be proud that you blew up a tank with a pistol.
alternatively you can weaken the tank enough for the enemy to abandon it so you can commit some good old grand theft panzer

thanks for reading my guide made out of pure boredom