Harry Potter: Quidditch Champions

The I’ve Always Wanted to Use That Spell achievement can be obtained by spending 10 skill points to upgrade a single role, the maximum amount of skill points that can be assigned to a role.

Skill points can be earned by leveling up your Career level by playing matches and earning medals. To spend your skill points on a role upgrade, from the main menu go to My Team > Select the role you want to upgrade and press A > Find a skill you want to get and press A to use your skill point. Note that for the Chaser role, which has multiple characters, the skills are shared between all three of your Chaser characters. Your Chasers cannot have different skills from each other, but you do not need to spend skill points on each one individually, adding a skill on one Chaser will add it on them all.

As soon as you spend your 10th skill point on one role, the achievement will unlock!

I hope this helps!