No worries, it's not a problem that you don't have much of experience. That you will gain, but you need to read documentation first. Connect to the console port to your switch, login as 'admin'. By default the password is empty.
Then check the document I've provided, page 6, "Logging in to the Web interface". I assume your switch as at factory defaults. What you need to do is to check what is the current setting of the default management interface, VLAN 1. Use 'summary' command. You will see the output similar to this:
<Sysname> summary
Select menu option: Summary
IP Method: DHCP
IP address: 169.254.1.2
Subnet mask: 255.255.0.0
Default gateway: 0.0.0.0
<Omitted>
If 'IP Method' is DHCP, then connect a network cable to port 1, for example. Another end of this cable connect to the network device that is DHCP server. Wait a minute. If IP address in the output is 169.254.x.x it means there is no DHCP server in your network and the switch assigned this autoconfiguration IP to itself. This is not what you want in general, so troubleshoot your DHCP server why it doesn't provide IP addresses. If IP address is valid (anything else than 169.254.x.x) you got the IP, bingo. Now you can try HTTP connetion to the switch.
If you want to assign IP address statically, or the IP has been set statically, but you want to change it to DHCP, use the same guide, page 30. The command you need is 'ipsetup'
If any doubts about configuration on the switch, just reset it to factory defaults by 'initialize' command in the same CLI