I tried to install linux on my system (linuxmint 20.3 based ubuntu) but it doesn't work straight. Some on this forum are saying you need to install some obsolete libraries in your system... That is a very bad idea ! do not do it ! I tried to install with "play on linux" the windows version, the install stop at the end with a run time error, but if you launch the game every thing works fine up to the end of the game ! Also you don't need to install the patches the game is all ready patched.

! ! !

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Tha same issue on Debian 12.
How I solved it:
- downloaded http: // archive.ubuntu.com/ubuntu/pool/main/o/openssl1.0/libssl1.0.0_1.0.2n-1ubuntu5_amd64.deb
- upnack it (you can use Midnight Commander)
- create a lib folder in the game folder (eg ~/Games/gog/baldurs-gate-enhanced-edition/lib)
- copy the content of CONTENTS/usr/lib/x86_64-linux-gnu (from libssl1.0.0_1.0.2n-1ubuntu5_amd64.deb) to the new created lib folder in the previous step
- edit start.sh
- after the CURRENT_DIR definition add: export LD_LIBRARY_PATH="$CURRENT_DIR/lib/"
This is how my start.sh looks
...
# Initialization
CURRENT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
export LD_LIBRARY_PATH="$CURRENT_DIR/lib/"
cd "${CURRENT_DIR}"
source support/gog_com.shlib
...

Now just start the game with ./start.sh