How to choose a word so that it is not between other words?

Question

Regular Expressions

I need to replace all expressions of the word "If" except when it is inside a word.
IfOtherwise - we do not replace
SomethingIfNotThat - we do not replace

And these we replace
If Not
If;
(If)
If=
=If
etc.

I can't figure out the regular expression.
Everything seems to be simple, but for example this [^A-z] If [^A-z] captures spaces and the service characters themselves, but only the word is needed, everything else should remain in its place.

Answer 1

Something like this, but it's like this:(?<=[^А-яёЁ]|^)Если(?=[^А-яёЁ]|$)

Answer 2

/\bЕсли\b/So?