More information can be found at Command Line Interface (CLI)

Point 1: To configure Break-Out

> enable
# configure terminal
# interface ethernet ?
R2-R8-LEAF01 [standalone: master] (config) # interface ethernet ?
<Device/Port>[-<Device/Port>]
1/1/1
1/1/2
1/1/3
1/1/4
1/3/1
1/3/2
1/3/3
1/3/4
1/5/1
1/5/2
1/5/3
1/5/4
1/7/1
1/7/2
1/7/3
1/7/4
1/9/1
1/9/2
1/9/3
1/9/4
.....
.....
1/25
1/26
1/27
1/28
1/29
1/30
1/31
1/32
# interface ethernet 1/25 shutdown
# interface ethernet 1/26 shutdown
# interface ethernet 1/25
# (config interface ethernet 1/25) # module-type qsfp-split-4 force

The resulting interface will become

Ethernet 1/25/1
Ethernet 1/25/2
Ethernet 1/25/3
Ethernet 1/25/4

Speed configuration can be found at

interface ethernet 1/25/1
# speed 25G