Default Extract system.img and NON-HLOS.bin

I tried using 7zip, extractnow and some random program I found on google called ext4_unpacker.exe. I want to extract the system and dig through and edit the files and the same thing with the modem.

I get cannot open as archive with 7zip, "unknown file format" with ext4 unpacker and it just won't open with extractnow.

thanks for the help in advance. and apologies in advance I know this is super noobish but the programs just won't work
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