I have a laptop which only has a vga output, I want to connect the monitors to the laptop using the vga simultaneously with a projector but once I add the third monitor the signal gets distorted, how do I solve such
Your monitors and projector may (probably) have different native resolutions. With a single output, you can only pick one resolution. Usually you have to pick the projector resolution. For a situation like this, you might want to look at getting a USB3 video adapter -- https://www.amazon.com/Plugable-Graphics-Multiple-2048x1152-1920x1080/dp/B00A2E1MQA