What nonsense are you talking about. If you want xiaomi.eu ROM for free, don't buy a device with MediaTek SoC.
The rules for providing xiaomi.eu ROM are clearly stated on this forum.
You are the one who should adapt, not the xiaomi.eu ROM developers.
Because ROMs are primarily intended for CN devices.
If you have a Global device you do not need this fix if you install any derivative of the Global ROM (TU,TW, RU, MI, EEA, ID, etc).
You would have to use it if you installed the stock CN ROM.
fastboot flash modemfirmware_ab modemfirmware.img
Or use my tool and swap the file. https://xiaomi.eu/community/threads/fix_sim_-xiaomi-14-global-verzion.72887/post-725922
The problem is that the Indian ROM does not yet have Android 15. The file I provided you is from Android 14. It may not work.
If you have a CN device and have installed the Global ROM, you need to install the "modem and modemfirmware" files from the CN ROM.
I think it would be much more convenient for you to install the xiaomi.eu ROM...