How to access LXDE GUI?

I managed to install LXDE on a Raspberry pi 3 b+ using DietPi but I can’t get it to boot into GUI.
I am connecting to it from my Windows computer using SSH and when I type startx it gives me the below message.
Basically what I’m trying to do is setup the lightest GUI on the Pi and be able to access it from my computer.

X.Org X Server 1.20.4
X Protocol Version 11, Revision 0
Build Operating System: Linux 4.15.0-48-generic armv8l Raspbian
Current Operating System: Linux DietPi 4.19.118-v7+ #1311 SMP Mon Apr 27 14:21:24 BST 2020 armv7l
Kernel command line: coherent_pool=1M 8250.nr_uarts=0 snd_bcm2835.enable_compat_alsa=0 snd_bcm2835.enable_hdmi=1 snd_bcm2835.enable_headphones=1 bcm2708_fb.fbwidth=720 bcm2708_fb.fbheight=480 bcm2708_fb.fbswap=1 vc_mem.mem_base=0x3ec00000 vc_mem.mem_size=0x40000000  console=tty1 root=PARTUUID=2fed7fee-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet net.ifnames=0
Build Date: 05 June 2019  12:49:54PM
xorg-server 2:1.20.4-1+rpt1 (https://www.debian.org/support)
Current version of pixman: 0.36.0
        Before reporting problems, check http://wiki.x.org
        to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
        (++) from command line, (!!) notice, (II) informational,
        (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.2.log", Time: Tue Jul  7 21:06:49 2020
(==) Using config directory: "/etc/X11/xorg.conf.d"
(==) Using system config directory "/usr/share/X11/xorg.conf.d"

Hi,

many thanks for your request. This is all working as expected. Typing startx into a SSH session will launch the desktop for a direct connected monitor. But if I understood right, you would like to connect remotely from you Windows machine. For this you would need to setup RealVNC on your RPi and install RealVNC client on your Windows system. This way you will be able to connect to the RPi desktop remotely.

ahh… Thank you for pointing me in the right direction. I have been trying to figure this out for ages!
Just to confirm, I would still need LXDE installed to use RealVNC with a GUI interface or is it LXDE not needed?

You could uninstall everything for LXDE. Using dietpi-software will pull all dependency for RealVNC later on.