Does training an LLM on a variety of different languages improve its reasoning and understanding in other languages?

For example, if GPT-5 (or whatever next gen model) was trained on a staggering amount of high quality Norwegian tokens that talk about medicine, city life, romance, maths, etc... would it be able to apply those concepts & learnings to other languages?

I'm trilingual and have ~100% of transfer of knowledge/reading I learn/read in one language into the others, curious to see if LLMs are like that.