I've got that book too. Some of the exercises are things that have definite correct answers: Circle all the 1st inversion chords in the provided example. Circle the cadence. What type of cadence is it? Some of them are more subjective and have more than one right answer: Using the given soprano line, create three lower parts that follow the rules of voice leading.
Matheus, you might be able to purchase a teacher's edition of the book, which would have correct answers to the exercises that have definite correct answers.
You may also be able to find some free online music theory tests which will have similar exercises and give you immediate feedback on your answers, so you can be sure you are understanding the concepts correctly.
Purchasing a second music theory text by a different author may also be helpful, so you can hear the same basic concepts explained in slightly different ways. Sometimes that can reveal any misconceptions you had about the material.
More and more colleges are starting to create online courses that are inexpensive (at least compared to going to university full-time), and open to students anywhere in the world. There are generally graded homework exercises that you complete online and receive the correct answers to after you finish, so you can tell if you are understanding the material. That would be another avenue you could explore.
Keep looking for explanations in as many different places as possible. You will start to have a better sense of the whole. But I'd agree that asking for homework correction every day here will make people tired very quickly. And might get us in trouble if a student in an official class for a grade at some university, using the same text, discovers our helpful set of correct answers and stops doing their own work. Try to find answers on your own, and then ask specific questions here if you are really doubting your understanding and feel stuck.