Why is my CD drive keep ejecting when the laptp is turned on?

This could be numerous things. Have you tried writing anything to the disc? If you have you may have files. Waiting to be wrote to the disc. Go to the DVD drive in My Computer by double clicking the icon. If there are files waiting to be wrote to the disc they will be shown there. You can either delete them or write to the disc.

You should also run a virus scan. You can use free utilities like malwarebytes. Another way of checking if you have a virus problem is by booting into the BIOS screen and see if the drive opens on its own or not. If it doesn't there is a chance you are infected. Otherwise it will probably be a hardware problem. To get into BIOS restart the computer. When the computer turns on and displays the first screen, there should be some writing on the bottom like F2 setup or something. You can click the F2 button a couple times and it should bring you to BIOS. Make sure to press the F2 button BEFORE the first screen dissappears.

As a last resort you could always go to Toshibas support and get the driver for the drive. And then go to Control Panel > System > Device Manager. Look for the CD drive and then right click and click delete. Confirm you want to delete it. The driver may be an executable so you can go to your downloads folder and find the file. Right click it and choose Run as Administrator and let it install.

Can you try the first two at least and see what happens and report back?