As a beginner, there are several factors to consider to “ease you into” the game. At the starting level, given your lack of skill, you would want a more “forgiving” set of clubs. This would mean opting for more flexible shafts, higher loft, and larger head sizes.
Oversize golf irons were designed for the beginner. The more solid, heavier head offers you a larger sweet spot, making it much more “forgiving”, and makes it easier to be able to play a reasonable shot. As your technique improves over time (and your handicap), you will find you start lacking the control you want once you have achieved more distance. By then you simply move on to a smeller head size.
When it comes to buying oversize golf irons, remember that harder is better. The harder the construction material, the more “forgiving” the club will be. It is best to go for stainless steel or titanium. Keep in mind, however, that titanium is rather expensive. So if you see a cheaper set boasting titanium heads, chances are it’s not high quality, and might even only contain a small percentage of titanium.
Oversize golf irons were basically designed to be easier to hit. As a beginner, control over distance is not a high priority. Due to your lack of skill it does not make much difference at this stage. You just want to be able to get the ball out there, and keep it in play. As your game improves, you will come to rely more on your swing, and less on the weight of the club. Then you can move on.