Cocoapods installation error in terminal

I’m trying to install cocoapods and these happens help me to resolve
currently I’m using macOs mojave 10.14.6
(base) nikhils-MacBook-Air:~ nikhilshekhawat$ sudo gem install cocoapods
Building native extensions. This could take a while…
ERROR: Error installing cocoapods:
ERROR: Failed to build gem native extension.

current directory: /Library/Ruby/Gems/2.3.0/gems/ffi-1.12.2/ext/ffi_c

/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/bin/ruby -r ./siteconf20200324-6597-m7dqf7.rb extconf.rb
mkmf.rb can’t find header files for ruby at /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/lib/ruby/include/ruby.h

extconf failed, exit code 1

Gem files will remain installed in /Library/Ruby/Gems/2.3.0/gems/ffi-1.12.2 for inspection.
Results logged to /Library/Ruby/Gems/2.3.0/extensions/universal-darwin-18/2.3.0/ffi-1.12.2/gem_make.out

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