As a dhampir, you are resistant to any and all magical effects that inflict the Charmed effect.  You also have resistance to necrotic and poison damage.

Due to their vampiric heritage, a dhampir can sometimes succumb to their parentage's thirst for humanoid blood.  While dhampirs can go for several years without even tasting a drop of blood, every once in a while they give in to their urges.  Many have taken to eating condensed blood packets and capsules to suppress those urges.  Because of this, dhampirs rarely, if ever, have to eat regular food to maintain their energy.

In combat, if a dhampir drops below half its total hit points, it must make a Wisdom saving throw (DC 10 or half the damage taken, whichever is greater) or succumb to its vampiric urges.  During this, the dhampir gains the Bite attack (attack modifier is Strength), dealing 7 (1d6+4) piercing damage plus 10(3d6) necrotic damage on a successful attack.  This lasts for 1 minute.  At the end of each of its turns, the dhampir can repeat the saving throw, ending the effect on a success.

One of the downsides to a dhampir's vampiric heritage is the fact that they can't stay out in the sun for too long (1d10 days).  If a dhampir is in the sun for prolonged periods of time without finding some form of shade, they begin to suffer from Sun Sickness.  While Sun Sickness won't kill a dhampir outright, they suffer similar issues to any other race that becomes exhausted.

The six levels of Sun Sickness are the same as the Exhaustion status.  For quick reference:

Level 1:  Disadvantage on ability checks.

Level 2:  Speed is halved.

Level 3:  Disadvantage on attack rolls and saving throws.

Level 4:  Hit point maximum halved.

Level 5:  Speed reduced to 0.

Level 6:  Death.

Sun Sickness can be reduced by spending a long rest in a shaded area, such as under a tree in a forest or inside a structure like a tavern.  Clothing such as a hat can hold off the effects of Sun Sickness by 1d4 days.

A dhampir reaches adulthood at the same time as the race the vampire parent mated with, and can live for several centuries after.

Your Strength score increases by 2, and your Intelligence score increases by 1.

Dhampirs can be of any alignment, though most tend to lean towards the true neutral side so as to avoid any undue attention from both vampires and other races.

Your size is Medium.

Your base walking speed is 30 feet.

Because one of your parents was a vampire, you have darkvision up to 60 feet.

You can speak common and 1 other language of your choice, based on which race your vampire parent mated with to produce you.

A dhampir can cast the following spells, using Intelligence as the spellcasting ability:

Darkness (1/day)

Misty Step (1/day)