"My kids want to play Fortnite, Roblox & Minecraft".
Here it is. Exactly what you want. Will play the games the kids want without breaking the bank.
Specs: 
CPU: Ryzen 5 5500GT
GPU: Radeon Graphics 7
MB: MSI/ASUS/GB B550
RAM: 16GB DDR4-3200 C19
SSD: 500GB Gen4 NVME
PSU: 400w+ 80+
Case: Tempered glass side, mesh front, full programmable rainbow ARGB fans.
Windows 11
AC WiFi