God’s power is infinite; He is omnipotent – all powerful. (Re 19:6) There’s nothing He wishes to do which He’s unable to do, and since God is good, He will do what is good, everything which is appropriate for Him to do.
This does not mean every imaginable task which can be formulated is doable: no, God can’t make a rock so big He can’t lift it, because the task is inconsistent with the nature of omnipotence. Rather than being distracted by nonsense, we ought to focus on the revealed nature of God.
Clearly, in creating the universe, time and space, God tells us a bit about Himself. He spoke the entire universe into existence; Earth and Heaven, the sun and moon, creating trillions of galaxies, expressed almost as an afterthought. (Ge 1:14) What might tax His strength, strain Him, even in theory? It is inconceivable.
God is outside of space and time, defining and establishing all possible dimensions, and well beyond them. He fills all things. (Ep 4:10) Every aspect of His creation obeys Him perfectly (Ps 119:91), following the purpose He assigned and aligning with His decrees; He’s holding all of it together. (Col 1:17)
We rightly extrapolate from God’s limitless power in the physical universe to the metaphysical: God is unlimited in His ability to work in and through the human will (Pr 16:9): He is utterly sovereign. (Da 4:35) Nothing happens outside God’s control (Ep 1:11); it’s all by His permission, for a glorious, ultimate purpose. (Ro 8:28)
Our free will operates within this sovereignty as God restrains us according to His purpose. (Pr 16:1) Even the most brutal, torturous death of the one, perfectly innocent Person, the worst crime ever committed by mortal man … God Himself was the willing victim, and He ordained it for His glory. (Ac 4:27-28)
A key purpose of this doctrine, in addition to moving us to eternal worship, is to establish our hearts in trusting God, that we not be anxious, frustrated or fearful. Worry and fear is acting out the lie that God’s unable, or that He’s not good. If we’re able to pray for something, and it’s good for God to do it, God is able to perform it, and He will (1Jn 5:15) — no matter what it is. (Ep 1:19)