Club length
US Kids Golf publishes a height-to-set chart. Use it.
A starter set in the right length range matters more than the brand.
Used clubs are common and fine. The right length is everything.
Glove
Sized by hand circumference. The glove goes on the lead hand (left for right-handed players).
Should fit snug, no bunching at the palm.
Shoes
Spikeless golf shoes for kids. Simpler, more versatile, kinder on the parking lot.
A regular athletic shoe works at first. Spikes only when the kid is consistent enough to need them.