Mental or physical
A genie gives you four wishes as a thank you for saving it, albeit, unknowingly. You can pick one selection from each four, mix and match or all mental or all physical.
1 - Speak, write and read one language and it's dialects (but not language family) fluently, or, know one martial art as if you were a top tier professional.
2 - Be at the peak of physical fitness including weight for your own bodies capabilities and it stays in that shape no matter what, or, your IQ is increased to 160 permanently.
3 - Play one musical instrument (or sing) at a world-class virtuoso level with perfect pitch and the ability to improvise freely, or, possess the flexibility, balance, agility, skill and grace of a top-tier gymnast or professional dancer permanently.
4 - Have the creative talent and skill of a bestselling author or renowned artist in one chosen creative medium (writing, painting, composing, etc.), or, have the hand-eye coordination, reflexes, and precision of a top professional athlete in a skill sport (tennis, golf, archery etc)