I don't completely agree with the guy above.
Sure, modern TF like the Movie TF can scan to be many things, but the character who got stranded should have "chameleon" as a special talent like DotM Lazerbeak to be THIS effective.
The modern TF Still have a fixed mass and some basic body characteristics that he have to keep in mind while scanning an altform. That why Optimus Prime chosed to scan a truck while Starscream chosed to scan a jet.
In my headcanon, if a modern TF get stranded in say, the BW planet, he'll be ginormous compared to the rest. That a plus for power, but a flaw from hiding. Then, if he don't and cannot have a flight mode, he'll have no choice to scan a beast mode to be more effective. The scanning would be much easier to do if he encounter local TF that do have beast modes.
However, even with the other's help, the only beast mode he should be able to acheave will be mechanical looking. Like the Dinobots or classic/Prime Insecticons or even Ravage. Also, that altmode will be way out of scale. Still, the newfound powers and abileties of such an altmode would be enough.
As for sustenance, he will NEVER be able to eat and digest organic matter like the others. However, the world is ro full of energon, just standing there will be enough for him to feed.
Depending on the TF allegance and personality, he'll end up being a

or

. If he's a bad guy, his power and size will almost guarantee him leadership.
So, tl;dr, yes, a modern TF will have big chances of survival. Remember that TF will surely be a war veteran, trained to survive in any situations.