My son turns 1 in a few weeks and he cries during the night wanting to sleep on my pillow. I brought him a cot pillow today, how should I introduce it to him?

At one year of age your son is no longer at risk of SIDS - as per definition.
Sudden Unexpected Death in infancy (SUDI) is the death of an infant less than 1 year of age.
SUDI includes SIDS & fatal sleep accidents.

https://rednose.org.au/article/what-does-sudden-unexpected-death-in-infancy-sudi-mean
https://rednose.org.au/article/what-is-sudden-infant-death-syndrome-sids

Red Nose recommendations for pillows are very general.
It is safer to wait until the child starts to sleep in a bed before introducing a pillow or other soft bedding.
https://rednose.org.au/article/at-what-age-can-i-introduce-cot-bumpers-and-pillows