Can I add a new language by the Language Pack Edit
 

I want to add the English language in this File DEWAV25_GEMINI_PCB01_GPRS_MT6225_S00.V866_L100_M6_ 16m_Es_Id_Th_Vn_Pt_Ar.B0M
you please explain how do I add a new language

thanks

Usually firmwares to Chinese phones contain the English language, once you do not, just try to find a similar firmware to Infinity Support.
If you can not find, you can themselves translate any of the available in firmware languages into English manually in Editor.