What's the best alternative language choice for Javascript developer?


Front-end engineer here for many years with Computer Science background but not coded much in server programming languages.

I have an upcoming interview with one of the big tech guys.

I will taking up the coding interview in JavaScript so need some thoughts on which book would be closest to understand and implement in JavaScript?

Exposed to Java more than Python in previous years though no way near to be comfortable taking coding interviews in either.

Need some thoughts on which language is closer to do a conversion to JavaScript?

Thanks for the help!