How can I pray to a deity who millions of others pray to?
“Bro, if I'm praying to God along with millions of others at the same time, how will he choose or come me? He must be SOOO busy answering prayers from the whole world, right? “
Valid question - and our scriptures answered it centuries ago, so here's the tea.
First, Nyaya Darshan says we jivas, embodied souls, have a manas - an inner organ that's atomic, partless, and can only contact one sense faculty at a time.
Which is a fancy way of saying your inability to multitask isn't a personal flaw, it's literally your hardware. Ishvara has no manas at all. His knowledge is nitya - eternal, non-sequential, all at once. You're a one-to-one connection. He's like a broadcast. A radio tower transmitting to ten people and ten million transmits exactly the same - because nothing is being divided per listener.
There's no queue, because queueing is a side effect of having a mind like ours.
Second, that image of God sitting somewhere up in the sky, straining to hear you across a distance? Not our model. The Brihadaranyaka Upanishad 3.7.15 and the Bhagavad Gita 18.61 call him the Antaryamin - the inner controller, seated in the hearts of all beings. When you pray, nothing has to travel. He's already the witness to the thought before it becomes words.
And as Krishna says in Gita 13.34 - yathā prakāśayaty ekaḥ kṛtsnaṃ lokam imaṃ raviḥ - as one single sun illumines this entire world. The sun doesn't pick which field to shine on. It doesn't shine less on you because it's also shining on someone else.
Third, and this is the part nobody tells you - the Brahma Sutra has an entire section called the Vaishamya-Nairghrinya Adhikaran. Literally, "on partiality and cruelty." Sutra 2.1.34 asks your exact question and answers it: he can't be partial, because he's sapeksha - he dispenses with reference to your own karma, not his preferences. And Shankara's own analogy here is rain. Rain falls equally on every field. Rice grows rice, barley grows barley - the difference isn't favouritism in the rain, it's what was already in the seed.
He's the common cause. Your karma is the variable. So he isn't picking favourites out of a crowd. There is no crowd. There's only your own ledger.
And fourth - when he does show up, from Prahlada to Dhruva, that's Kripa. Grace. And he never rations it. When Krishna multiplies himself in the Rasa Lila so every single gopi has him completely, undivided - that's prakasha. Each manifestation whole, the original undiminished.
This is the Isha Upanishad's purnam adah purnam idam - that is whole, this is whole, take the whole from the whole, and the whole still remains. Infinity minus infinity is still infinity. He doesn't split his attention a billion ways. He gives a billion people all of it.
So the next time you fold your hands and wonder if anyone's listening - the one you're calling isn't far away and busy. He's the one doing the listening, from inside. Keep your sadhana going.