I am a new player creating a rogue tiefling which gives me the thaumaturgy cantrip. From my understanding you can't cast spells or cantrips without being something like a wizard.
- Can I cast this cantrip?
- Is it the same for spells I learn with the race? (Hellish Rebuke and Darkness)
Best Answer
Yes: Class features are not the same as spell slots
This is a character racial ability, which is independent of any class features. You don't have to choose a spell casting class to use a racial ability. Cantrips are always available to use, but the game needs to relate it to an ability score due to how spells generally work mechanically.
Your Tiefling can be of any class. (Spell caster or not). Any number of racial features that embody spell-like abilities are available regardless of the class a PC has. Other races have similar features, shown here for comparison.
Tiefling: Infernal Legacy
Forest Gnome: Natural Illusionist.
Drow: Drow Magic.
High Elf: Cantrip.
None of these racially granted abilities has any class restriction attached to it (gnomes, tieflings, high elves, and drow are more naturally magical than other races). The spells do not require a spell slot, but do require that a long rest be taken between uses (unless they are a cantrip, which is a level zero spell per Chapter 10 of the PHB).
These racial features are similar to, but different than, benefits like the Dwarven Resilience (resistance to poison and advantage versus poison saving throws, PHB p. 20). They are available regardless of the PC class chosen.