Usage patterns
〈人〉が会社に入るfor someone to join a company
He joined this company last year.
会社で働くto work at a company
My sister works at a large company.
会社に勤めるto be employed at a company
My father is employed at a trading company.
会社を経営するto run/manage a company
会社を設立するto establish/found a company
She established a company in her twenties.