Can I apply for the new E-Visa system while in Thailand, and how does it work?

Say you’re here on an elite visa that is expiring a d you want to convert to a marriage visa , would you be able to do that without leaving Thailand

For countries free visa to thailand will it still be free to shop to thailand from across the border or do we need to pay visa? Would anyone know?

The best way to look at the evisa system is as if it were a physical consulate but instead of walking through the gate you walk in electronically. That means you should be in the country you want to apply at and should remain in that country until the process completes

There is no "new" evisa system. They're just finishing converting the final handful of countries that haven't been using it for the past years already.

You apply for a Thai visa based on the Thai embassy that services where you physically are. Obviously there is no Thai embassy in Thailand. You must go to a country and apply for a Thai visa through the embassy that services that country.

You cannot activate a visa from an embassy in Thailand. You activate a visa when you enter Thailand by handing it to the immigration officer along with your passport.

Nothing has changed for 99% of people whose Thai embassy at home has already been using evisa for years.