He first started studying under his father and the scholars of Damascus, he memorized the Qur-aan at a young age and studied Hadeeth, Fiqh, Usool and Tafseer. He was known to be intelligent and have a strong memory at a young age. He went on to study and become erudite in other sciences, the conditions of a Mujtahid were present in him at a young age, it was not long before he became an Imaam who was recognized by the greatest of scholars of his time - at the age of thirty.
A more complete biography of the Shaykh can be found here.
His student Ibnul Qayyim stated:
‘A group of people who love the Sunnah and knowledge asked me to compile a list of all the books that the Shaykh, the Imaam, the ‘Allaamah, the Haafidh – may Allaah be pleased with him – wrote, so I told them that I failed to compile a list gathering them all…’
He then said: ‘From what I have seen of his works in Tafseer…” he then mentioned 93 books.
‘From what he has authored in Usool…’ he mentioned 20 books.
‘From what he has authored in ‘Qawaa-‘id and Fataawa…’ he mentioned 145 books.
‘In Fiqh..’ he mentioned 55 books.
‘In Wasaaya and Ijazaat and booklets relating to different sciences…’ he mentioned 22 books.
A program consisting of 37 of the books he authored can be downloaded here.
وقد بدأ بطلب العلم أولًا على أبيه وعلماء دمشق ، فحفظ القرآن وهو صغير ، ودرس الحديث والفقه والأصول والتفسير ، وعرف بالذكاء وقوة الحفظ والنجابة منذ صغره. ثم توسّع في دراسة العلوم وتبحر فيها ، واجتمعت فيه صفات المجتهد وشروط الاجتهاد منذ شبابه، فلم يلبث أن صار إمامًا يعترف له الجهابذة بالعلم والفضل والإمامة ، قبل بلوغ الثلاثين من عمره.
فإن جماعة من محبي السنة والعلم سألني أن أذكر له ما ألفه الشيخ الأمام العلامة الحافظ – رضي الله عنه – فذكرت لهم أني عجزت عن حصرها
ثم قال
فمما رأيته في التفسير فذكر اثنين و تسعيب مؤلفا
و مما صنفه في الأصول فذكر عشرين مؤلفا
قواعد و فياوى فذكر خمسة و أربعين و مائة
الكتب الفقهية و سرد خمسة و خمسين مؤلفا
وصايا و إجازات و رسائل تتضمن علوما بلغت اثنين و عشرين
يمكنك أن تحمل موسوعة مؤلفات الإمام ابن تيمية هنا.