My laptop has power and the the power button on the keyboard lights up but when i start it there is no graphics. Its just a black screen and i dont see any BIOs 
i installed ram and m2ssd and also setup the keyboard and the screen cover thing at my own. Please help
What are the exact specs of your machine? Mainboard, SSD, Ram, OS you’re trying to install, etc. Have you taken any troubleshooting measures like reseating the ram or SSD? If it’s an AMD board they can take a very long time to boot for the first time.