I have a modem, a LAN cable, a laptop, an iPhone 4 and the iPhone's usb cable. Can I use my iPhone to connect to my modem's internet?
No. The peice missing from your array is a wireless router. Unless you are able to create a hotspot from your laptop. iOS devices can only connect to a network wirelessly.
Yes. I beleieve I can create a hotspot from my laptop. If it is successful however, how would my iPhone connect to it? By bluetooth?
WiFi. The phone can not connect to the Internet via bluetooth.
Retrieving data ...