i have two arduino mega and they send data to each other by an I2C connection. But one of those arduinos is connected to an ethernet shield which allows it to send data to a web server. Being both connected does that mean that they both can send or access the web server. Sorry if any ambiguity was found but I didnt find a better way to ask this question.
I2C does not automatically share resources between two connected devices. You would not be able to share an Internet connection from a Mega connected via I2C to another Mega which has an Ethernet shield.
However, you could write code for both Megas that implements a two-way communication in which the non-shield Mega sends requests or commands to the one with the Shield, and then passes that data back to the non-shield Mega.
However, you, as the coder, would be responsible for designing such a protocol and implementing it. It would be quite a task probably.