stride in like (someone) owns the place

Translations
войти как будто (кто-то) владеет местом
He strode in like he owned the place, commanding everyone's attention.
Он вошёл, как будто владел этим местом, привлекая внимание всех.
Definitions
To enter a place confidently and assertively, often with an air of entitlement or self-importance, as if one is in charge or has authority there.