Jack of All Trades (5e Feat)
From D&D Wiki
Jack of All Trades
You have spent your life trying to learn from people of all skills and all walks of life. When you finish a short rest or long rest, you can choose up to two skills, tools, or weapons you are not proficient in. You must spend at least 30 minutes training yourself with another character who is proficient with the chosen skills, tools, or weapons, and willing to teach you.
Until you choose another set of skills, tools, or weapons, whenever you make an ability check that involves the chosen skill or tool, or make an attack roll with the chosen weapon, you add half your proficiency bonus to the roll. You do not gain this benefit if the roll already includes your proficiency bonus.