I am also facing the same issue while installing Magento 2.3.3 in my localhost - XAMPP Server. It's successfully installed, but when I opening the admin panel, it appeared a blank screen like the below image.
Admin Panel
The Solution is:
After that, I changed the code like below.
Go to this Path: ..\vendor\magento\framework\View\Element\Template\File then Open this file Validator.php
Then Search this line $realPath = $this->fileDriver->getRealPath($path);
Replace to $realPath = str_replace('\', '/', $this->fileDriver->getRealPath($path));
Image for reference to change the Validator.php file
Now Admin Panel will appear successfully.
Admin Panel appeared, but the issue is Magento logo does not appear on the login screen. After logging the admin Admin Panel, Icons don't appear on the dashboard also its continuously loading like the below images Icon Don't Appear
The solution is:
Go to this Path: ..\app\etc then Open this file di.xml
Then search this line
Magento\Framework\App\View\Asset\MaterializationStrategy\Symlink
To Replace the line
Magento\Framework\App\View\Asset\MaterializationStrategy\Copy
Check this image for replacing the code & Make sure the code should come like this image
Now Go to the Admin Panel and Refresh the page. It's Successfully working without issues. All icons have appeared also Logo is appeared.
Admin Panel Sucess image
Now Go to Client Area, if you update sample content, the page looks like this image Client Page with Sample Content. Otherwise, it will appear like "CMS homepage content goes here".
Everything is working good.
I hope it will use to solve this issue.