I Can Load Magical Powers and Martial Arts

He traveled through time and became a bad gambler. After being severely beaten by his creditor, he forced the protagonist to join the underground black boxing industry. Fortunately, the infinite card library system was accidentally activated, and you can collect martial arts and increase martial arts experience through observation/combat/asking for advice. Therefore, the protagonist relied on the martial arts in the Baji Martial Arts School to successfully win the underground boxing ring. He also later learned many martial arts to strengthen himself, and finally embarked on the road to slay demons and cultivate immortality step by step.