Question:
Shalom rabbi, I saw that answered that a Bnei Noach can make a tattoo on his body, Would you have the source of this permission please?
Answer:
Hi,
The reason is because Benei Noach are basically commanded to do seven mitzvos, and although there are othre mitzvos that they accepted upon themselves this is not one of them.
Have a good day
Sources:
There is controversy if there are other mitzvos that the gentiles accepted upon themselves See Chullin 92, Margolio Hayam Sanhedrin 56a-24, Torah Temima Bereisis 2-16 (39), and Rama M'pano - Chakor Bdin 3-21, Toldos Noach Chap 1-6. However even according to that, not having a tattoo is not one of those mitzvos.