Gfilui

I am connected to a LAN. I am able to connect to it by WiFi but I am unable to connect it by ethernet cable. I have dual booted Ubuntu with Windows 8.Everything works fine in Windows 8.But I am unable to use it in Ubuntu. The output of lshw -C net is

*-network 
 description: Ethernet interface
 product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
 vendor: Realtek Semiconductor Co., Ltd.
 physical id: 0
 bus info: pci@0000:01:00.0
 logical name: enp1s0
 version: 15
 serial: 50:7b:9d:d6:94:fb
 size: 10Mbit/s
 capacity: 1Gbit/s
 width: 64 bits
 clock: 33MHz
 capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
 configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half firmware=rtl8168h-2_0.0.2 02/26/15 latency=0 link=no multicast=yes port=MII speed=10Mbit/s
 resources: irq:127 ioport:5000(size=256) memory:a1204000-a1204fff memory:a1200000-a1203fff
 *-network
 description: Wireless interface
 product: RTL8821AE 802.11ac PCIe Wireless Network Adapter
 vendor: Realtek Semiconductor Co., Ltd.
 physical id: 0
 bus info: pci@0000:02:00.0
 logical name: wlp2s0
 version: 00
 serial: a8:a7:95:a4:22:3b
 width: 64 bits
 clock: 33MHz
 capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
 configuration: broadcast=yes driver=rtl8821ae driverversion=4.13.0-36-generic firmware=N/A ip=192.168.8.171 latency=0 link=yes multicast=yes wireless=IEEE 802.11
 resources: irq:132 ioport:4000(size=256) memory:a1100000-a1103fff

Output of ifconfig:

enp1s0 Link encap:Ethernet HWaddr 50:7b:9d:d6:94:fb 
 UP BROADCAST MULTICAST MTU:1500 Metric:1
 RX packets:322 errors:0 dropped:1 overruns:0 frame:0
 TX packets:775 errors:0 dropped:0 overruns:0 carrier:0
 collisions:0 txqueuelen:1000 
 RX bytes:30856 (30.8 KB) TX bytes:72032 (72.0 KB)

lo Link encap:Local Loopback 
 inet addr:127.0.0.1 Mask:255.0.0.0
 inet6 addr: ::1/128 Scope:Host
 UP LOOPBACK RUNNING MTU:65536 Metric:1
 RX packets:6000 errors:0 dropped:0 overruns:0 frame:0
 TX packets:6000 errors:0 dropped:0 overruns:0 carrier:0
 collisions:0 txqueuelen:1000 
 RX bytes:18095859 (18.0 MB) TX bytes:18095859 (18.0 MB)

wlp2s0 Link encap:Ethernet HWaddr a8:a7:95:a4:22:3b 
 inet addr:192.168.8.171 Bcast:192.168.15.255 Mask:255.255.240.0
 inet6 addr: fe80::24ac:ff57:68ab:7f44/64 Scope:Link
 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
 RX packets:4903501 errors:0 dropped:0 overruns:0 frame:0
 TX packets:51878 errors:0 dropped:0 overruns:0 carrier:0
 collisions:0 txqueuelen:1000 
 RX bytes:434024015 (434.0 MB) TX bytes:9039737 (9.0 MB)

Ok, so from the ifconfig output your problem is that you did not set up your LAN.

You can see in the last block that you have an IP address for your wifi (192.168.8.171). You LAN (section enp1s0) does not have that. That means your network is not configured. You have not IP address, so I can not work.

You need to Create a new network connection, provide DHCP or Manual Setup and data possibly data like IP address, Network Mask, DNS Server and Gateway address.

Network Configuration in Ubuntu is a very basic task that can be done from the GUI. You will need information from your Unviversity about the Parameters to use, likely DHCP, but I would not know.
There are excellent descriptions including pictured of the dialogs and what to put where, imho it would not be useful to reitereate it here in full length. As they are plenty of sources, please consider looking up the Ubuntu users guide, wiki or Youtube tutorials on "Ubuntu LAN Setup" or "Ubuntu Ehternet setup". I am almost sure your university will provide to How-To sections on how to configure the network, maybe thats you best bet because it will give your the correct parameters as well.

Hope it helps.