Dragonborn

Age, Young Dragonborn grow quickly. They walk hours after hatching, attain the size and development of a 10-year-old human child by the age of 3, and reach adulthood by 15. They live to be around 80.
Size, Dragonborn are taller and heavier than humans, standing well over 6 feet tall and averaging almost 250 pounds. Your size is Medium.
Speed, Your base walking speed is 30 feet.
Hardened Scales, Your Ac increases by 1.
Draconic Resistance, You may pick one damage type from Acid, Cold, Fire and Lightning. You gain resistance to this damage type.
Languages, You can speak, read and write Common and Draconic.

Subraces

Chromatic Dragonborn

Breath Weapon, when you take the Attack action on your turn, you can replace one of your attacks with an exhalation of magical energy in a 30ft line that is 5ft wide. Each creature in that area must make a DEX saving throw (Dc = 8 + your CON mod + your proficiency bonus). On a failed save, the creature takes 1d10 damage of the type associated with your draconic ancestry. On a successful save, it takes half as much. This damage increases by 1d10 when you reach 5th level (2d10), 11th level (3d10), 17th level (4d10). You can use your Breath Weapon a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.
Chromatic Power, when you make your breath weapon attack you can use your full action to empower the attack. The empowered attack extends to 15ft wide and deals an extra 1d10 damage. Anyone who fails their save suffers an additional effect from the list below, depending on the damage type;

Corrosive (Acid), The target’s Ac is lowered by 1

Frozen (Cold), The target’s movement speed becomes 0 until the end of their next turn

Burning (Fire), The target takes 1d6 fire damage at the start of their turn until they take an action to put out the fire

Shocked (Lightning), The target is affected by the stunned until the end of their next turn

Poisoned (Poison), The target is poisoned for 1 minute.

Once you use this trait you can’t do so again until you finish a long rest.

Metallic Dragonborn

Breath Weapon, when you take the Attack action on your turn, you can replace one of your attacks with an exhalation of magical energy in a 30ft line that is 5ft wide. Each creature in that area must make a DEX saving throw (Dc = 8 + your CON mod + your proficiency bonus). On a failed save, the creature takes 1d10 damage of the type associated with your draconic ancestry. On a successful save, it takes half as much. This damage increases by 1d10 when you reach 5th level (2d10), 11th level (3d10), 17th level (4d10). You can use your Breath Weapon a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.
Metallic Warding, as an action, you can channel your draconic energy to protect yourself. For 1 minute, you become immune to the damage type associated with your Draconic ancestry. Once you use this trait you can’t do so again until you finish a long rest.