Magic Weapons 5e spell requires you to touch nonmagical weapon. The spell will continue until the weapon is turned into a magical weapon. You will get the +1 bonus on damage and attack rolls.

At Higher levels:

You can cast the d&d5e magic weapons spell by using the spell slots from 4th level or higher. The bonus will be increased to +2. The bonus will rise to +3.

Casting time 1 Bonus action
Classes Paladin, Wizard
Components V
Concentration Yes
Time As little as 1 hour
Higher Spell slot Desc If you cast this spell with a slot of 4th or higher level, the bonus will increase to +2. You get +3 bonus points if you use spell slots that are 6th or higher.
Niveau 2
Name Magic Weapon
The Range Touch
School Transmutation
Target A nonmagical weapon