Working from home due to Covid & code confliction issue

Hello github, I am new here, Actually my boss asked me to work with a team which is remote. we are working from home due to the Covid. Our project is already hosted on name cheap, my questions is how our team mates (3 developers) work on same project which will merge directly on server after updation without any confliction. Right now we are working vai ftp which cause too many conflicts and end up with mess. Do you have any solution for this? please let us know. Thank you

Use proper version control.