This was already sufficiently answered above but I wanted to share some information from the comics the MCU is directly based on so people that are unfamiliar have some frame of reference.
MCU Ironman is very strongly based on the Extremis arc in the comics, which included a new origin story for the Ironman armor where in the post 9/11 world Tony Stark's weapons are being used to fight Al Qaeda and after an incident during an inspection he is injured by one of his own bombs and is kidnapped by terrorists in Afghanistan.
That part you already should be familiar with, the movies present that part of the story verbatim but the rest is a quick recap/summary of what follows and how it's presented in the comic and translated in the MCU.
The suit that he uses in Avengers: Infinity War is the MK50 AKA the Endo-Sym suit which in the comics is the most advanced version to date of Ironman's armor, specifically it is designed to compliment a Tony Stark who has Extremis.
To understand the suit and how it works in the comics, you also have to understand that the Extremis storyline was a similar but very different thing in the films, in the comics it was an attempt to recreate the Super Soldier Program that created Captain America with a sort of biological nanotech.
I can understand why they wanted to keep all that of out of the MCU but the short version is that in the comics (that MCU Ironman is most strongly based) on Tony Stark has Extremis, therefore he HAS a healing factor, but he also in fact developed his own version of Extremis which also gave him the ability to interface directly with machines, they left a lot of this out in the films but the basic components of the storyline are essentially in tact as is the functionality of the MK50 Ironman armor.
In the comics this suit is like the ultimate suit for a Tony Stark that has Extremis and interfaces directly with technology. The MK50 Ironman armor in the comics is based off the Venom Symbiote and nanotech. It's described and looks like a sort of a liquid smart-metal suit very similar to the t1000 liquid metal Terminator. While the suit doesn't quite have a mind and personality of it's own, it's a sort of biotechnological prothesis and is very much alive.
In the MCU, Tony Stark doesn't have Extremis but the MK50 still functions very similarly as seen in the film. So with some limitations (there's only so many nanobots it has to work with) it can form into any configuration (in the comics, the armor can even grow into a new version of sorts of the Hulkbuster armor) giving Tony use of virtually any tool he might need on the fly, one would assume including advanced medical equipment.
Of course the MCU doesn't explain any of this technology in detail and it just borrows elements from the Extremis arc and comics that followed it, so you're intended to fill in the blanks yourself and suspend your disbelief. But all the basic elements of that storyline and the tech in it are present in the MCU...just reconfigured. Instead of Tony having Extremis + cool symbiote suit, he has this nanotech suit.