Language requirements - B1 or C1?

B1 German is more commonly known as intermediate German, while C1 German is advanced. B1 level learners have a basic understanding of the language and are able to communicate in simple everyday situations, such as ordering food or asking for directions. At this level, learners will be able to understand most of what they hear and read in everyday conversations. They can also express themselves with some detail on familiar topics.
C1 level German learners are considered fluent speakers who can converse fluently about an array of topics. They can understand spoken and written texts on complex subjects with ease and produce clear, well-structured speech without much effort. Additionally, they may be capable of using idiomatic expressions accurately when speaking or writing in the language.
The main difference between B1 and C1 German is the level of proficiency. B1 learners are still considered beginners, while C1 learners have a much higher level of fluency in the language. Additionally, C1 learners will be able to understand more complex topics and express themselves with greater accuracy than those at the B1 level.