You didn't mention your specs, but since it's 6 years old, definitely get a new computer. You probably can't upgrade to any modern hardware. If you're good with computers, you can build your own and it would be a lot cheaper.
iPhone 8: Everything we know so far
This is all the iPhone 8 reports and rumors in one place. From a 5.8-inch OLED display, reports of wireless charging and even a 3D scanner for facial recognition, it's all here.