Connect two devices on the same board throught I2C or SPI
I would highly recommend you team up with somebody that has experience in this area. You might even be able to find a mentor. What you are asking is very difficult to answer because of all the data, design criteria, etc needed to make a successful product which you have not supplied. There is no such thing as simple lines, they represent circuit connections that go from point to point to convey information, power and ground.You need to prototype this first, debug your hardware and software before committing to a PCB (Printed Circuit Board). I recommend you spend the next few weeks watching tutorials on line covering basic electronics and each of the items you propose to use, and build some of them with your prototyping equipment.