Heroes of Archetype
Clarifications - All
From Basic Rules, pg. 60
A spell scroll bears the magical words of a single spell, written in a mystical cipher. Using an action to read the scroll allows you to cast the spell without components.
If the spell written on the scroll appears on your class’s spell list, and the spell’s level is one that you can normally cast, you cast the spell successfully. Otherwise, you must make an Intelligence (Arcana) check to see if you can successfully cast it. The DC equals 10 plus the spell’s level. On a failed check, reading the scroll only consumes its magic with no other effect.
The level of the spell written on the scroll determines its spell’s saving throw DC and attack bonus, as shown on the following table: