Search string within strings but regex ain't cutting it.

[arulrajesh]

I have a python script that will take a query in this (https://drive.google.com/file/d/11gt0x5aMIGf5qJB0rrqICO4ZVq8fUjtB/view?usp=share_link) language and convert it to a regex pattern. The regex is then used to match in another string(a transcribed phone conversation).

The regex have become unwieldly.
I have been trying to understand the ANtlr4 book for the past week, but haven't gotten very far.

how would I go about writing a grammar for this in antlr4?