Hi there yes when the switches are stacked they act as one large switch. There can be a max of 8 switches in a stack.
If you create a VLAN (E.G. DATA) and want to add 4 ports to it as native you would do this.
DATA - SUBNET 10.1.2.0/24
DATA - TAG 30
#This creates the VLAN and configures the IP address
create vlan DATA
configure vlan DATA ip address 10.1.2.1/24
configure vlan DATA tag 30
# This add the ports to the VLAN as native/untagged.
# Adds Switch 1 Port 1, Switch 2 Port 10, Switch 3 Port 14, Switch 4 Port 23
configure vlan DATA add ports 1:1, 2:10, 3:14, 4:23 untagged
# Optional enable ip forwarding on the VLAN
enable ipforwarding vlan DATA