Level 1 No Saikyou Kenja ~Noroi De Sai Kakyuu Mahou Shika Tsukaenaikedo, Kami No Kanchigai De Mugen No Maryoku O Te Ni Ire Saikyou Ni~

One day, Haruto Saijou was forcefully transmigrated and cursed by a god from another world. A world of swords and magic. In this world you get stronger by increasing your battle levels. But due to a curse, Haruto is unable to gain levels. However, due to a mistake by the evil god, Haruto was able to obtain an inexhaustible supply of magic… (Source: Shousetsuka ni Narou, translated)