What does it take to brute force something like this
What you have shown above is 42 hex characters, which is 21 bytes, which is 168 bits. Therefore, if you know nothing else about the structure of the data, you have 2^168 different possibilities to brute force.
As an illustrative example, suppose that you could leverage the entire peak hash rate of the bitcoin network to try and brute force this hash. Suppose that rate is 200,000,000,000,000,000,000 hashes per second. Or, if you aren't hashing, suppose you have some insanely massive hardware system that can make 200,000,000,000,000,000,000 attempts per second. (Again, this large rate value is just an example of a rate of a very very powerful system--way more powerful than you can afford.)
Even in this pie-in-the-sky example, if would still take you about 60 billion trillion years to brute force the 21 byte value. So, effectively, it is impossible.
I can brute force anything else like
iambad, blackapple1, etc
The first example is just six lower case letters. If you are restricted to six lowercase letter, then there are only 26^6 possibilities. As you can easily check, 26^6 is way way fewer than 2^168. Similarly, in your second case, if you know that "blackapple1" always follows the pattern of: dictionary-word+dictionary-word+single-integer then there are only about nine billion possibilities to brute force. Again, as you can easily check, nine billion is way way fewer possibilities than 2^168.
But how can I brute force something like that line?
As discussed above, effectively, you can not.