Make sure to unplug all external devices from the laptop.
Try an SMC reset. If the laptop can power on, then also try a PRAM reset (hold the PRAM reset for a full minute so it activates several times).
If this does not work, then you will need to take the laptop to Apple or an Apple Authorized Service Provider for repair. You may want to take the HDMI cable along as well to be examined in case it is the source of the problem or it might show symptoms of the damage.
For your other electronics, unplug them and hold the power button for each device for 10 seconds. Leave these devices unplugged for 10 minutes. Disconnect the cables connecting them to each other. Try powering on each device individually to see if they even respond, then connect them back together. Try other non-hdmi video cable options if they are available to bypass any damaged hdmi ports. Does your TV power on without any video cables or antenna source connected where you can access the TV's menus?