Syncing PHP application with local System to cloud System & remote database access and data transfer

We have application developed in PHP & My SQL and currently hosted on Linux based cloud platform with webpanel installed. We have a local server that is on windows 2012 OS with xampp installed. Both the servers have common PHP application deployed. Now we have to keep an automated sync system between offline server (based on windows) with online server (with Linux ) so that the all files made on offline server are synced to online also same way all changes and files created/edited along with the data given in database synced with offline server (when ever there is internet connectivity) Another task need to be done is we have local server with multiple systems in local network. Now there are some PHP Mysql databases on other systems. The server need to access those databases and sync data in real time to Main database in windows environment This has to be done by 23-1-18 by morning 11 am. PHP development team is ready to support. Local windows server access will be given in team viewer and online linux server access shall be given. Please ping for any further clarifications.