There are three different kinds of Arcade games: Quick Match, War and Sniper Training.
In Quick Match, you are thrown into a mini zone somewhere on Erangel, and there are different variations : Item Heaven (with Airdrop weapons in high density), All Weapons, Shotguns only, Pistols only and Melee.
In War, there are about 20 players, and you are thrown onto either Stalber, Mylta Power, Mylta factory building, Ruins, Shooting Range, Quarry, Mansion, Shelter, and Georgopol Mountain. The location varies every game. The aim of the game is to have the most points possible at the end of the game (about 10 minutes) - you get points by killing players and reviving teammates. You have infinite spawns. It is either ARs (M416, AKM, SCAR-L and M16A4), SMGs (Vector, UZI, UMP45 and Thompson SMG) and finally sniper (Kar98K only). There are airdrops.
In Sniper training, you are thrown into a mini zone significantly larger than that of Quick Match. You can find Pistols, Throwables, Mosin Nagant Sniper Rifles, M24 and AWM, as well as all scopes in the Bolt Action variation. In the Semi Automatic variation, you can also find Mini-14, QBU, SLR, SKS, Mk14 and VSS.