Basically msh, we'll use something called "Point Buy" to determine your character's Ability Scores. This calculator lets you do that: chicken-dinner.com/5e/5e-point-buy.html
If you select "Human" it should automatically apply your Human +1 boost to all scores.
Strength is how strong you are, Dexterity is how fast and nimble you are, Charisma is your people skills, Wisdom is how much street smarts and insight you have, Constitution is how many hitpoints you have and how tough you are, and Intelligence is how smart you are.