Send Push notification To Specific Users (Devices) iOS

iOS
1

how can send push notification to specific users i know that i have to create a channel for user but the thing is that , that i’m assigning a unique groupId to user’s who qualify certain conditions say that i have Users:

name
user 1
groupId
group1

name
user2
groupId
group1

name
user3
groupId
group2

name
user4
groupId
group1

name
user5
groupId
group4

as you can see here we have 3 users from same group now how can i send my notification to only those users who are in group1

P.S.
i think i need this but how to specify whom to broadCast ??

deliveryOptions.setPushBroadcast()
2

You should create a channel for each group and register the users to receive the messages from corresponding channel.