PC help

so I built my first PC and I ran into a problem. my fans turn on but there will be no display nor can i connect a key board and mouse. the Dram LED will light up and thats were im stuck if anyone knows how to fix this respawn to this.

system
CPU:i5-10400
ram: DDR4 2666MHz 16GB
PSU: Thermaltake smart series 700w
motherboard: prime B560M-A
SSD: 500GB pci-Express 3.0