The SCHUFA problem
New to Germany = no SCHUFA score. This is like 'no credit history', not 'bad credit'. Explain this in your cover letter. Alternatives: Creditreform or similar from home country, bank reference, employer guarantee.
Involve your employer
Many international companies help with relocation: guarantees, landlord contacts, temporary housing. Ask HR! A letter from your employer with salary confirmation in German is gold.
Furnished apartments as a start
Easier to get, no furniture needed, often no long contract commitment. More expensive per square meter, but makes sense for the first period. Homelike, Wunderflats, Spotahome are reputable providers.
Translating documents
Employment contract, income proof, references - everything in German or English. Certified translations rarely necessary, but must be legible. Use German template for cover letter.