ESP8266 with a GPS module (such as the popular NEO-6M) and a BMP280 sensor, along with a web server to display the data

Are you saying that your life is at risk if you don't get this project working ? I find that hard to believe

So far you have started a topic in the wrong place, not used code tags when advised to do so and have not even told us what the problem is with your code

Start by using Edit/Auto Format in the IDE then Edit/Copy for Forum to copy and add the code tags and post the code into a new reply here. In that reply tell us the problems that you have with the code