"University of third age" courses are most likely not for credit, though might be a good idea to ask them anyway, at least they will have something to fill into their FAQ section.
(Some universities actually offer Czech language online courses for credit but I'm not so sure whether the exams would be also online, more likely not.)
(Some universities actually offer Czech language online courses for credit but I'm not so sure whether the exams would be also online, more likely not.)