(Not a Teacher)
1- "His blade caught the sunlight and shone with a dazzling radiance." Not sure if that's quite what you're looking for, but it sounds appropriately flowery at least.
2- Infantry is fine. You could call them footmen, if you'd like. What kind of infantry are they? Are they dismounted knights? Are they using pikes or bows? There are more specific terms.
Student or Learner