If you're just using fastboot/adb for flashing, etc, (and not for actual development ), don't bother with platform-tools, etc., but just use something like - https://forum.xda-developers.com/t/o...1-4-3.2588979/ .

If double-click bat file doesn't work, just open the bat file with notepad and find the place whwre it says the fastboot commands, (near the end, "fastboot flash boot..." "fastboot flash system..."), and copy/paste into terminal one-by-one.