Question: how to connect my laptop to my tv with an hdmi cable?
Answer: Power on your laptop and TV (both with HDMI port) and prepare a HDMI cable.
Plug HDMI cable into both your laptop's and TV's HDMI ports.
Now you may see your TV with blue screen showing No signal message. Press INPUT or SOURCE button on your TV remote. ... 
Step4. Now on your TV, you may see the same screen with laptop.