You could use https://en.wikipedia.org/wiki/Yacc

I decided to write my own lexer/parser/compiler it's pretty straightforward.

Sources I use(d) to program this, e.g look at resulting assembly from other compilers or look at how the AST is generated for other languages.

https://en.wikipedia.org/wiki/Recursive_descent_parser

https://en.cppreference.com/w/c/language/operator_precedence

https://godbolt.org/

https://astexplorer.net/

I didn't start writing C yesterday, and most of the things are just stuff I've learned over the years and seeing how other languages work and then just use what I know to try to program in a logical manner.

Also I've written a implementation of a scripting language (compiler and VM) before in similar fashion.

https://github.com/riicchhaarrd/gsc