Your spouse and minor children can usually join you in Germany through family reunification (Familiennachzug) — the smoothness depends on your permit type and your paperwork.

The core requirements (for the family of students/workers):

Your residence permit must be valid for a year+ ahead (Blue Card holders have the easiest path)
Sufficient income to support the family without public funds — checked concretely against your net payslips
Sufficient housing — roughly 12m² per person; your studio won't work
Health insurance for everyone
Spouses joining most permit holders need basic German (A1) before the visa — with notable exceptions (e.g. Blue Card spouses are exempt)

The process: your family applies for the family reunion D visa at the German embassy in their country while you prepare the German side (housing, income proof, sometimes a declaration at your Ausländerbehörde). Appointment waits at busy embassies can be long — book immediately, prepare documents while waiting (marriage/birth certificates need apostilles + certified translations, and both can only be organised in the issuing country).

Once here, your spouse generally receives full work permission — an underrated feature of the German system.

This is the one process where professional advice can pay off — migration counselling services (Migrationsberatung) are free in every city.

Red flags:

Certificates without apostille and certified translation stop family visas cold — and both must be organised in the issuing country. Start there, before anything else.
Income maths done on gross salary — the office counts net income against the family's needs. Run the numbers honestly first; a failed application costs months.
Discovering the spouse-A1 requirement after booking the embassy appointment — check whether your permit type is exempt first, and start the course in parallel if not.
Paying "family reunification consultants" for what the free Migrationsberatung does professionally.
A flat that's too small on paper — the ~12m²-per-person housing check is real; move first if needed.