I across some websites that offer change of our IP addresses. It says, we can surf net anonymously, including changing our IP address and location. Most of the softwares are not free, so I have not try it out yet. But my question is, so, IP addresses will no longer be unique or valid for identify which computer were sending/request the information?

I though only the ISP can determine our IP, so we can change our IP from some commercial softwares huh?

Case:

If I change my IP address, I go to a website which is supposed to be banned by my country, will the ISP let me pass the check and I will be able to browse the website which should be blocked?

another question:

From what I know, if we want to go to certain website, here is the flow:

My Computer => ISP => Website => ISP => My computer

I am not sure, if its the correct flow, but I am sure that, whichever website I want to visit, I need to go through my ISP, isnt it?. So if we change out IP, our ISP will record our new IP or the original(assigned-by-ISP) IP?

Sorry for my bad English.