3 easy way to prove the Earth is round

1- Go out in the countryside at night, take a picture of the starry sky then change hemisphere and compare the two star skies, there will be no common point, which proves that according to our position the sky changes totally, the earth is therefore round .

2- Otherwise, ask yourself why we have seasons which differ according to the North and the South, and the earth is round and has its tilted axis of rotation. This is why the seasons vary according to the poles. Impossible if the earth was flat.

3- Still not convinced? Here is a shocking and verifiable argument if you have an internet connection (you have it if you are reading this answer)
Take a flat earth map