Your battery might be dead. Try plugging your charger in to your computer and then turning it on again. If that works, you might just need to charge your battery. If you have your charger in and the computer turns on but the battery isn't actually storing any power, you will need to replace your battery. There is a guide for replacing a battery at the following link: HP Envy 17-3070nr Battery Replacement If using the charger doesn't fix the problem and you know the charger isn't broken, then try referring to the troubleshooting page for this laptop at the following link: HP Envy 17-3070nr Troubleshooting

That's my favorite movie! The problem could be that your fan assembly is not working properly and needs to be replaced. Your fan might just have accumulated a lot of dust and needs to be cleaned. If your fans are making a lot of noise and whirring loudly, that might be an indicator that you are close to overheating. There is a guide on how to do replace your fan assembly at the following link: HP Envy 17-3070nr Fan Assembly Replacement