Citation generators can be useful resources when you are working with citations. Unfortunately, these generators are often not 100% accurate and depend largely on the user inputting the information you correctly. Generators are not able to determine if you used the right case usage or edition. If you choose to use a citation machine always double-check your results!
Also, keep in mind that citation generators are often run by for-profit companies that may request payment for their services.
What style you use in your papers will largely depend on your professors' preferences, or if you are publishing, the requirements of the publication. However, certain subjects tend to use certain styles.
Biology- APA or AMA or CSE