Does the Hadith "Whoever seeks knowledge to compete with scholars, or to argue with the ignorant, or to make himself appear important in gatherings and show off" apply to one who seeks knowledge with the aim of refuting those who attack religion, in order to advise them and uphold the truth?

The summary of the Fatwa:

The text of the Hadith is: "Whoever seeks knowledge to compete with scholars, or to argue with the foolish, or to attract people's attention to himself, Allah will admit him into the Fire." A similar warning is mentioned in the saying of the Prophet, peace be upon him: "Whoever learns knowledge by which the Face of Allah Almighty is sought, but he only learns it to obtain a worldly gain, will not find the fragrance of Paradise on the Day of Resurrection."

As for reading and preparing to respond to disbelievers and those who propagate falsehoods, this does not fall under this warning, because responding to them is an obligation. Islam has commanded the preparation of strength, as Allah Almighty says: "And prepare against them whatever you are able of power and of steeds of war by which you may terrify the enemy of Allah and your enemy."