GNU/Linux Mint 20 Realtek rtl8822BE Driver Installation Guide
Hi! The linked Tutorial shows you Step-by-Step How to Install Realtek rtl8822BE Wireless Driver in Linux Mint 20 GNU/Linux.
And the Realtek rtl8822BE Linux Mint 20 Driver Installation is Quick & Easy, involving at most the execution of some Basic Shell Commands.
Please be aware of how this Driver is Not supporting all the Linux Kernels range, so in case of issue consult the available Online Documentation.
So as a possible Solution, then you may also see: How to Install New Kernel Guide.
Again, in case of Issue for preventing any possible Driver loading Interference you should also take into account: How to Blacklist Kernel Modules.
Realtek rtl8822BE Driver Linux Mint 20 Installation Guide