Installing cocoapods to macOS Catalina

In my mac mini I've running Catalina 10.15.7. I've also installed Xcode 12.4. Now as I'm using third party library I'm trying to install cocoapods in my mac. So I used this - sudo gem install cocoapods which I got from official website. But I'm getting this - Password: Fetching concurrent-ruby-1.1.8.gem Fetching fuzzy_match-2.0.4.gem Fetching i18n-1.8.10.gem Fetching thread_safe-0.3.6.gem Fetching tzinfo-1.2.9.gem Fetching activesupport-5.2.5.gem Fetching nap-1.1.0.gem Fetching httpclient-2.8.3.gem Fetching algoliasearch-1.27.5.gem Fetching ffi-1.15.0.gem Fetching ethon-0.12.0.gem Fetching typhoeus-1.4.0.gem Fetching netrc-0.11.0.gem Fetching public_suffix-4.0.6.gem Fetching addressable-2.7.0.gem Fetching cocoapods-core-1.10.1.gem Fetching claide-1.0.3.gem Fetching cocoapods-deintegrate-1.0.4.gem Fetching cocoapods-downloader-1.4.0.gem Fetching cocoapods-plugins-1.0.0.gem Fetching cocoapods-search-1.0.0.gem Fetching cocoapods-trunk-1.5.0.gem Fetching cocoapods-try-1.2.0.gem Fetching molinillo-0.6.6.gem Fetching atomos-0.1.3.gem Fetching colored2-3.1.2.gem Fetching nanaimo-0.3.0.gem Fetching xcodeproj-1.19.0.gem Fetching escape-0.0.4.gem Fetching fourflusher-2.3.1.gem Fetching gh_inspector-1.1.3.gem Fetching ruby-macho-1.4.0.gem Fetching cocoapods-1.10.1.gem Successfully installed concurrent-ruby-1.1.8 Successfully installed i18n-1.8.10 Successfully installed thread_safe-0.3.6 Successfully installed tzinfo-1.2.9 Successfully installed activesupport-5.2.5 Successfully installed nap-1.1.0 Successfully installed fuzzy_match-2.0.4 Successfully installed httpclient-2.8.3 A new major version is available for Algolia! Please now use the https://rubygems.org/gems/algolia gem to get the latest features. Successfully installed algoliasearch-1.27.5 Building native extensions. This could take a while... ERROR: Error installing cocoapods: ERROR: Failed to build gem native extension. current directory: /Library/Ruby/Gems/2.6.0/gems/ffi-1.15.0/ext/ffi_c/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby -I/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0 -r ./siteconf20210406-1384-1vtmk4p.rb extconf.rb checking for ffi.h... *** extconf.rb failed *** Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options. Provided configuration options: --with-opt-dir --without-opt-dir --with-opt-include --without-opt-include=${opt-dir}/include --with-opt-lib --without-opt-lib=${opt-dir}/lib --with-make-prog --without-make-prog --srcdir=. --curdir --ruby=/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/$(RUBY_BASE_NAME) --with-ffi_c-dir --without-ffi_c-dir --with-ffi_c-include --without-ffi_c-include=${ffi_c-dir}/include --with-ffi_c-lib --without-ffi_c-lib=${ffi_c-dir}/lib --enable-system-libffi --disable-system-libffi --with-libffi-config --without-libffi-config --with-pkg-config --without-pkg-config /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:467:in `try_do': The compiler failed to generate an executable file. (RuntimeError) You have to install development tools first. from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:585:in `block in try_compile' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:534:in `with_werror' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:585:in `try_compile' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:1109:in `block in have_header' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:959:in `block in checking_for' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:361:in `block (2 levels) in postpone' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:331:in `open' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:361:in `block in postpone' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:331:in `open' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:357:in `postpone' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:958:in `checking_for' from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:1108:in `have_header' from extconf.rb:10:in `system_libffi_usable?' from extconf.rb:42:in `' To see why this extension failed to compile, please check the mkmf.log which can be found here: /Library/Ruby/Gems/2.6.0/extensions/universal-darwin-19/2.6.0/ffi-1.15.0/mkmf.log extconf failed, exit code 1 Gem files will remain installed in /Library/Ruby/Gems/2.6.0/gems/ffi-1.15.0 for inspection. Results logged to /Library/Ruby/Gems/2.6.0/extensions/universal-darwin-19/2.6.0/ffi-1.15.0/gem_make.out I've seen this question but my ruby version is - ruby 2.6.3p62 (2019-04-16 revision 67580) [universal.x86_64-darwin19] I've also take a look in this but could not able to solve the problem. **Edit:**
I've used this - xcode-select --install but got - xcode-select: error: command line tools are already installed, use "Software Update" to install updates So, Is there any ruby dependency I've to install first or I just missed something?