Hey @ursNani
You can use split function for the above scenario.
Here is how my flow looks like:

LineSpace Compose: Added to remove fields which are extracted with a line space.

Compose:
Contains the input that you have given above.

Compose 2: To remove square brackets.
Expression Used: replace(replace(outputs('Compose'),'[',''),']','')

Compose 3: To remove extra part that we dont require.
Expression Used: split(outputs('Compose_2'),'First Name : ')[1]

FirstName: To extract first name.
Expression Used: split(outputs('Compose_3'),'Last Name : ')[0]

LastName:
Expression Used: split(split(outputs('Compose_3'),'Last Name : ')[1],'Email Address :')[0]
EmailAddress:
Expression Used: replace(split(split(outputs('Compose_3'),'Email Address :')[1],'Message : ')[0],outputs('LineSpace'),'')
Message:
Expression Used: split(split(outputs('Compose_3'),'Message : ')[1],'Phone Number :')[0]
Output:

CompanyName:
Expression Used: split(split(split(outputs('Compose_3'),'Company')[1],'Name : ')[1],'Postal Codes : ')[0]
PostalCodes:
Expression Used: split(split(outputs('Compose_3'),'Postal Codes : ')[1],'Area Of Interest : ')[0]
AreaOfInterest:
Expression Used: trim(replace(split(outputs('Compose_3'),'Area Of Interest : ')[1],outputs('LineSpace'),''))
I hope this helps 🙂
Sundeep Malik.
Looking for a New Job!!! Please Help!!!