Changing number of posts on remote feed

Using very simple PHP code (because that’s all I can handle) I have set up my remote website to display my most recent WordPress blog post. I would like to change the code to display the 2 or 3 most recent posts. I’m pretty sure this should only take a line or two of code. Can someone tell me if that’s right, what the code would be, and where in the code that would go? Many thanks