It appears that there are at least a couple of different models of the Inspirion 15 3000. There should be further numerical information which follows, like 3542, 3543, etc. Please look in the user manual which should have come with this computer to see what the full version is and post this information in your topic. When I was researching this I found that there were 15 3000 in July of 2017 which had Windows 8.1 installed on it and newer versions which had Windows 10 installed. Fortunately the two are similar enough that a lot of the troubleshooting applications can be used on both types.
You stated "The mouse works and scrolls around but when I click anywhere, nothing happens." Are you using an external mouse or the touchpad?
If you are using the touchpad, see if an external mouse will work, preferably a wired mouse.
Since this is a new computer which I would have to guess that it has little added to it at this point. For this reason I would suggest doing a Refresh using installation media. The instructions below include information to create your own installation media.
How to perform a Windows 10 Refresh from Installation Media
A Refresh will basically reinstall Windows 10. You will have the options to keep your personal files, but it will uninstall any third party programs you installed. You will be offered a list of the programs which will be uninstalled, you can use this list as a reference to these programs.
To do a Refresh on a computer which can not boot you will need Windosw 10 Installation Media.
If you don't have installation media you can use the Windows 10 Media Creation Tool to create installation media for either a disc or flash drive. Follow the instruction for the second option Using the tool to create installation media (USB flash drive, DVD, or ISO file) to install Windows 10 on a different PC.
In order to use either form of installation media you may need to change the boot order in the BIOS so that the type of media (disc or USB flash drive) is the first device in the boot order, and the ssd/hdd the second device.
If you are using a disc place it in the tray of your optical drive, close the door and restart the computer. When the computer recognizes the disc it will instruct you to press any key to boot from the disc.
If you are using a USB flash drive place it in a USB port and restart the computer. You will receive the message to press any key to boot from the device.
Connect the installation media you created to your nonfunctional PC, and then turn it on.
On the initial setup screen, enter your language and other preferences, and then select Next. If you're not seeing the setup screen.
Select Repair your computer.
On the Choose an option screen, select Troubleshoot. From there. Select Reset this PC.
There is a very good tutorial available, you will find it here.
Let us know what the outcome is.