My problem solved with delete arm64 from target>build settings>Excluded Architectures. Actually i deleted from there before, but actually worked when i go to my VSCode and go to ios/App/App.xcodeproj/project.pbxproj file and searched EXCLUDED_ARCHS = arm64; and delete from there, and worked, i dont know why my update at xcode did not worked but VSCode worked xcode 12.0.1, iOS 14 pack updated, and all capacitor stuff updated for 2.0.4 (latest one)

nothing worked for me, until go to VSCode(IDE APP), and ios/App/App.xcodeproj/project.pbxproj that file , and searched EXCLUDED_ARCHS = arm64; and delete that line, i did same thing from xcode, like go to target>build settings, exclude arc thing and deleted arm64 from there, didnt worked before, but deleting from VSCode worked , weird

i couldn't find the original post - thanks that person- manually install from that link solved my problem https://developer.apple.com/download/all/?q=command%20line%20tools

install manually from this link https://developer.apple.com/download/all/?q=command%20line%20tools solved my problem