Yes, it would be easier.
If they knew how many bits of entropy your password was, they could rule out passwords not under that entropy strength, and narrow down their search for your password.
No it does not, because if the attacker does not know the set of symbols used, knowing the entropy does not help them. I can tell you have an 32 bit (which is weak) password. You are no closer to knowing my password which could be made off words, numbers, latin alphanumeric symbols, special characters, cyrillic symbols, utf-8 or any mix of them. There is a theoretical advantage that you only need to test a subset of all possible passwords for each set of symbols, but you might still need to test a possible infinity number of symbol sets.
Also in order to brute force something you need the file. So if the question is whether you can tell someone your password strength, you can. Keep in mind though that the entropy depends on the way you generate a password. Selecting a random word from a list of 8 words, only has 3 bits of entropy no matter how long and complex the words are. If your password is not generated randomly it might be impossible to determine its entropy.
