I'm starting to use QGIS desktop and many other tools like Python, Geoserver or PostGIS as a Geo-information's master student and I want to know if can I get a better performance for these in Linux, refering to speed boost (based in benchmarks), difficulty to work with and difficulty to install packages.
I suspect you'll get a lot of subjective answers to this question, but here's some (hopefully objective!) points to keep in mind:
running Linux natively will always be faster than running it in a virtual machine, so dual booting will be the faster option if you want to run under Linux
Linux filesystems are usually much faster than Window's (source: the many benchmarks done by Phoronix comparing filesystem performance of the Windows Linux subsystem vs native Linux), so potentially there's a speed boost in running down heavy operations under Linux. A lot of GIS is still dial heavy (such as reading/writing large datasets), so there's a potential boost here in running QGIS under Linux.
Generally, the Windows graphics drivers are more heavily optimised and are faster than their Linux counterparts. This doesn't impact QGIs much, since most of the rendering done in QGIS is done on the CPU. The exception is the new 3D map views. So potentially, there's a performance boost in running QGIS on Windows for 3D map views.
Performance aside, it's usually much easier to get packages installed under Linux vs Windows. E.g QGIS on Linux uses the system Python install, so it's easy to add new libraries and have them available for use in QGIS. On Windows... it's not easy.
Compiling software is magnitudes easier on Linux. So if you need newer versions of tools or want to explore development versions of software, you'll find this much easier on Linux.
Windows is by far the most common operating system in use, and that's also true for GIS work. You'll find more available answers, blog posts, tutorials etc which apply to Windows than Linux.