External Antena use

I am trying to find our about if I should turn on my external router when working on Section 7. Network Penetration Testing - Post Connection Attacks, lessons 39, 40, & 41? If I do not connect it to a router, I can not find an IP address to use when trying to run the material on my computer. I am running ;“ip addr show wlano” to get a ip address to use and if I do have it turned on I get the following…

root@kali:~# ip addr show wlan0
4: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether 00:c0:ca:97:48:81 brd ff:ff:ff:ff:ff:ff
inet 10.18.100.99/16 brd 10.18.255.255 scope global dynamic noprefixroute wlan0
valid_lft 691020sec preferred_lft 691020sec
inet6 fe80::ecd8:4a18:37d0:b3c6/64 scope link noprefixroute
valid_lft forever preferred_lft forever
root@kali:~# ^C
root@kali:~#

If I run the same command and it is not turned on I get the following result…

root@kali:~# ip addr show wlan0
4: wlan0: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default qlen 1000
link/ether ba:41:37:63:7f:f1 brd ff:ff:ff:ff:ff:ff
root@kali:~#

and if I run ifconfig, I get the following…

root@kali:~# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 10.0.2.15 netmask 255.255.255.0 broadcast 10.0.2.255
inet6 fe80::a00:27ff:fe74:17d4 prefixlen 64 scopeid 0x20
ether 08:00:27:74:17:d4 txqueuelen 1000 (Ethernet)
RX packets 1393048 bytes 2011169733 (1.8 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 275311 bytes 17500569 (16.6 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10
loop txqueuelen 1000 (Local Loopback)
RX packets 322 bytes 42933 (41.9 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 322 bytes 42933 (41.9 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

root@kali:~#

any thoughts on what I am doing is right or wrong appriciated