Many jobs require the candidate to speak both German and English. I do not speak German, but I plan to take proper classes in January 2021. Does being fluent in German play a big part in general when it comes to hiring in Germany?
It depends on the job. If an employer wants a candidate to be fluent in German, you can't do anything about that (working in particular areas may require German based on a common sence). However, there are employers whose corporate language is English. OR a particular job can be fulfilled in English only. For you this means that you should focus more on this kind of openings. Don't waste your time and energy on roles where you don't have enough of qualifications (language is one of them).
Homework required: make a list of targeted companies or/and job, where English is the first language.