to learn contract bridge, I find the bcalc single/double dummy solver bcalc useful:
http://bcalc.w8.pl/index.php?lang=en&topic=downloadalso good is the freeware bride program Wbridge5, which has won several world computer bridge championships. It is a Windows program, but runs fine on linux with the wine emulation layer. (I've run it on fedora 30, debian 10 and ubuntu 19.10)