Some things were fictional in earlier movies, today those things are a reality today like smartphones, calls, video calls, computers, supercomputers, laptops, social media, T.V., Aeroplanes, cars, and motorbikes, etc.
1.J.A.R.V.I.S.
J.A.R.V.I.S. is Toni Stark's A.I. program J.A.R.V.I.S. is very intelligent from any A.I. programs. Tony Stark created it himself These things must have looked quite possible because now you have Google, Alexa, Siri, and Bixby like A.I. You have to see it in your smartphones, but it is the starting level because the commands are fed and A.I. The user does not have to pay any command fees while we are currently F.R.I.D.A.Y or J.A.R.V.I.S. Like A.I. Still far to make. But apart from this, A.I. Even now, Over time, a lot of power is getting filled like social media and ads algorithm and Internet Market Ads. And if there is an archive in making this, what will happen to A.I. Misuse your powers.
2.Arc Rector
Tony Stark's arc reactor in Marvel Cinematic Universe is like a heart that moves him and his suit and lives like a battery that can store a lot of energy to keep his suit running The more storage is needed to store more energy or More storage is required to store more energy and such technology does not exist yet.
3.Neno Technology
Tony Stark's suit in Avenger's infinity war was made up of Nanotechnology and his A.I. F.R.I.D.A.Y. With the help of that it becomes a form as the whole suit is made in advance, weapons, cannon, a shield, and sward can be changed and also can fly very well. And easy to use, durable, strong too and even now we have not been able to archive this technology.
4.Vibranium
In the MCU, a metal named Vibranium is found, which is found only in Wakanda, this metal can cause the vibration of any intensity, so it is used only in making weapons and this metal can only break the sharp Uru metal.
5.Universal Translator
The 10th movie of the Marvel Cinematic Universe which was released in 2014 in Guardians of the Galaxy Vol.1 or is said to have a Universal Translator on that planet so that everyone can speak and understand each other's language.