Is there a site or program to build regular expressions to match any string on the site?

Question

Regular Expressions

There is a site on which I need to find a line using regular expressions.
The code on which I use regular expressions = REGEXEXTRACT(INDEX(IMPORTHTML(D994;"table";0);2;1);"\d+\s*(?:-\s*)?(\S+)")
Is is there a site that would make the work easier
I know that there is a site https://regex101.com but it is not suitable for this purpose or am I missing something?

Answer 1

https://www.amazon.com/_/dp/0596528124?tag=oreilly20-20
https://www.amazon.com/Regular-Expressions-Cookboo...

Answer 2

What exactly is the problem?
Where is the code?
Where is the error?

Answer 3

Regular expressions are not a complex language. This is a design that can be studied in a couple of evenings.
There is hardly a site that would tell you how to parse other sites using regular expressions, because the global trend is such that now sites are not parsed with regular expressions.
They use libraries that work with the dom tree and extract data from it.
Therefore, you should not turn away so sharply from the fact that you are advised to read any book on regular expressions and just learn how to use them yourself.