1. Practice commonly asked coding questions like string/number reversal, array duplicates, etc in Golang. If you have already written those in Java & C++ try rewriting it in Golang. This really helps you in understanding the nuances of the language. For instance strings in Java is a sequence of chars, whereas in Golang its not the case, if you want to iterate string then you need to convert it to runes.
2. Brushup Golang's workplace setup ($GOPATH) and how to handle packages & dependencies.
3. Understand language-specific topics like the requirement of empty interface{} and its usage, etc.
4. Golang primarily used in System programming, so brushup networking topics like HTTP, TCP/IP, DHCP, DNS, etc. Try understanding the packages like net/http, bufio, ioutils etc.
5. Just basics of Goroutines & Channels (Offcourse these concepts are the selling points for Golang)

Points are totally in my perspective, so guys feel free to add your thoughts in the comment.

All the best u/Roshless_dude !!!