Hello and welcome to the forums!
1. You need to enter the license key in the vSphere Client: In the "Configuration" tab click on "Software/Licensed features" on the left, then on the "Edit..." link at the right top.
2. If you want to connect a CD-ROM/ISO of type "Client Device" then this can only be done while the machine is powered on. So, power on the VM first, then use the menu in its console to connect a local ISO file or a local CD-ROM drive. If booting is going too fast then reboot again by pressing Ctrl-Alt-INS at the console.
- Andreas