The easiest syntax to copy if you’re looking for a high level language is Smalltalk.
But most of the time, I wouldn’t even use that. Simple imperative languages that look like BASIC works pretty well in most domains. If you simplify the syntax a little, it’s very easy to understand the compiler and use it for say when you want users to input code into existing systems.
Syntax is a minor issue but something that people are very opinionated about. You could technically build multiple front ends that share the typechecking, CFG validation, optimization, register allocation and byte code emission phases. But it is too much work for what is presently a personal project.
also:
https://github.com/BaseMax/AwesomeInterpreter
and probably there is one for compilers too.
"ut" (https://github.com/s-i-e-v-e/ut) exists, but it is more of a POC for the syntax more than anything. So lexer+parser+typechecker. Did this during COVID in TypeScript but did not finish.