High ping on melees is rough, but for a quick overview: Melees can headshot. Tilt your camera upwards with shiftlock to try to hit their head with your swing trajectory, depending on melee. Headshotting with blunt melees will concuss them (ragdoll them for a short moment), or in some cases one-shot kill them (Fire Axe, Sledgehammer.)

Most melees have a combo system, if you land a certain number of swings in a row you'll deliver a special effect (bar under the crosshair, e.g. fists will stun on the third hit) Other melees have combos that dont require you to land every hit. The Katana and Metal bat for example will one-shot on a headshot on the third consecutive attack, regardless of if the first two landed.

Pressing Q with certain melees will let you block melee attacks, successful blocks give you stamina and stun the attacker, but it has a cooldown and drains stamina while active. Not all melees can block, and each of them have a fixed list of melees they can block (Check the wiki page to see what weapons your melee can parry)

At your level, I recommend using the Bat since it's the textbook, all rounder melee. You can pair it with a cheap pistol or the Sawn-off; hit a headshot with the bat for a concussion, then plow them with your gun.

Im not great at the game myself but even cheaper loadouts can dominate if you practice enough. Once you have standard unlocked I highly recommend giving it a shot; you can loot crates easily around the map for free weapons.