This is a great overview of the subject. The youtube video has the wrong title, it's not about Go for crypto developers, but rather Crypto for those using Go. Recommends using AES (hardware support) with GCM block cipher mode for encryption, bcrypt for hashing passwords, SHA2 for hashing with HMAC, and ECDSA/P256 for signatures (why not pgp?). There's a lot of older legacy stuff in the Go crypto libraries in stdlib which you shouldn't use unless you absolutely have to.
There's a link at the end to https://github.com/gtank/cryptopasta with some public domain examples of crypto code in Go.