golang-1.21 binary package in Ubuntu Focal amd64

 The Go programming language is an open source project to make
 programmers more productive. Go is expressive, concise, clean, and
 efficient. Its concurrency mechanisms make it easy to write programs
 that get the most out of multicore and networked machines, while its
 novel type system enables flexible and modular program construction.
 Go compiles quickly to machine code yet has the convenience of
 garbage collection and the power of run-time reflection. It's a
 fast, statically typed, compiled language that feels like a
 dynamically typed, interpreted language.
 .
 This package is a metapackage that, when installed, guarantees
 that (most of) a full Go development environment is installed.
 .
 To use this version, instead of the default one provided by golang-go
 package, add /usr/lib/go-1.21/bin/ to PATH, or invoke /usr/lib/go-1.21/bin/go
 directly.

Source package