In the name of God, the Most Beneficent, the Most Merciful
Your question: How can a muslim follow Quran and Hadeeth correctly?
You can read Quran correctly by ready page by page every day. You know, when you want to read your favorite novel, you just can’t wait to read it completely, after you bought it from library and after you opened your book the one you bought, you read it step by step till you reach the end of the book, the same way you do with Quran. For example, I read an interesting novel about police and I read it step by step till the end and now I learned what was about in this book. But it is much preferable for you to read Quran because, reading Quran is an Action and Sunnah means practices of prophet Muhammad (PBUH) that can be Wajib or Mustahab or Mubah. (Prophet was infallible and never did any Makruh or haram). sometimes Sunnah is used as meaning of Mustahab but this is general and not technical. After You have read Quran, you try your best to follow what you have read it. But, they must know that it is beneficial to follow Quran correctly because, they’ll get rewarded but if they do as they wish, they might get punished by God or forgiven.
The Messenger of God (blessings of God be upon him and his family) has said:
”The best of those amongst you is the one who learns the Qur’an and then teaches it to others.”
Imam Ja’far ibne Muhammad as-Sadiq (peace be upon him) has said:
”The Qur’an is the trust of God (given) to His creations, therefore it is desirable for every Muslim to look at this trust and to recite (a minimum of) 50 ayat (verses) of the Qur’an everyday.”
CONCLUSION: Try your best to read 50 ayats( verses) everyday. You’ll be able to follow Quran correctly when you have finished reading it.
I hope it is a good answer