It is useful to first consider what Brahman is. The first thing to know is that space exists as an infinite capacity and God Sri Krishna occupies part of this space. The Universe is the totality of what exists that can ever be detected by humans. The Hindu word for it is Parabrahman. Brahman is a word that describes the energy entity of the Universe (comprising distinct physical energy and consciousness energy components). So, is there anything more to the Universe than these two energies? Yes, the Universe in addition contains the invisible mind of God as Paramatma and God’s creative powers that channel the direction of universe. When Brahman comes to an end (its two energies get dissipated into wider space as it expands) God will withdraw the universe within Himself and go to sleep until He decides to create Brahman again.
The term infinite means what is beyond the detection capacity of humans. So the Universe by this definition is infinite. And Brahman being the sum of the physical energy and consciousness energy is also therefore infinite.
The production of matter within the universe of different shapes and constitutions by utilising Brahman requires the input of the mind of God as Paramatma with His creative powers. The universe functions to precise laws of Nature powered by God. In addition God can override the functioning of Nature through Maya or creative powers because God permeates the universe but is external to it. Thus, the universe should be viewed as the birth of an Entity from God. The Universe is currently infinite as it has extended into vacant space which is limitless and we humans cannot observe all of it. But it was finite once 13.5 billion years ago. God too is finite.
The Taittiriya Upanishad defines Brahman as Satyam Jnanam Anantam. It describes the religion of Brahmanism facililated and operated by the guna consciousness deity Brahma. Under the varna system of the Vedas Brahmins invoke Brahma through their rituals, yagnas and mantras. Sri Krishna is unmoved by these incantations, as He is only accessible when an individual transcends the gunas.