I use MIRC and this is my goal, i'm sure it's simple! thanks guys.
on $*:text:*test*:#: { msg $chan "Entire message containing test" }
You dont need the $ after the on, it's only used when you use regex to match (see here).
And indeed it's quite simple, use $1- to match he whole message. $1 will match the first 'token'.
In your example sentence Entire message containing test, $1 will rerturn Entire assuming you did not use a tokenize before and because the default delimiter is a space in mSL. $2 will retrurn message and so on.
Here is a great article about token manipulation and in your mIRC client you can use the command /help $1- to learn more about remote identifiers.