If you want to type in Unicode (Mangal) and convert it to EKLG, or vice versa, you will need a Unicode to Legacy Converter . You cannot type directly using Google Input Tools into an EKLG font setting without conversion software.
You selected EKLG font, but when you type, you see English letters instead of Hindi. Solution: This happens because you are typing in the English input mode. You need to switch your keyboard input to Hindi (Traditional) or use the Remington layout. EKLG maps English keyboard keys to Hindi letters (e.g., pressing 'd' might give you the Hindi letter for 'v' depending on the specific version).