You were a person who signed up for the Vault program and was in a vault when the bombs dropped.

 

You can pick from one of these vaults and each give you a bonus or decrease in stats.

Your player will not know until they pick

Vault 345: Everyone  was given a special vile that every day they would have to drink every day this will give the player plus one in STR

Vault 467: Every person was fed a pound of radroach  meat every every day making people take 1d4 less damage when damaged by rads

Vault 219:Every person was sent into the wastelands the ones who survived gain +1 in intimadation

Vault 331: every person was interjected with pure plasma every day giving them extra vision and speed (+10)

Tool Proficiencies: Guns

Equipment: Choose A or B: (A) Quarterstaff, Calligrapher's Supplies, Book (history), Parchment (8 sheets), Robe, 8 GP; or (B) 50 GP