That's an obvious first step, yes, and I'd be able to do it. They are a war crime to employ. But they are unfortunately effective as a defense against attack, that's why they're used. As long as they're around they're killing and maiming people, but if I just remove them all I could end up making things worse.
Second obvious idea, just disarm everyone — the problem here is that weapons keep getting into the country all the time. China, India, Israel, North Korea, the Philippines, Russia, and Ukraine were all recorded to be supplying weapons in 2019. If we just wipe out the stock that's present then whoever gets the weapons first wins. We could go so far as to wipe out weapons supply in all those places but at that point it's getting somewhat morally dubious to destroy weapons that might be used unethically and we're getting so fucking huge that there's no way something doesn't go wrong we haven't thought of.
Third obvious idea, partition the country somehow with landforms. Put in fuckoff huge mountain ranges and separate all the combatants by allegiance and ethnicity, get the people being persecuted their own chunks of land. This might work but I feel like they'd figure out a way over the ranges somehow, and it'd destroy the geography. If you supplied enough temporary supplies it might work but it'd still be a clusterfuck. And it's politically poison and will separate many people from their relations etc etc. Think of East and West Germany and the Berlin Wall and all the pain that caused everyone who suffered it. Think of Israel and Palestine, too.
Fourth obvious idea, number three but dump them all in an ocean somewhere with their own personal landmasses — the problem here is that without constant resupply from me and good distribution systems everybody starves, plus making a landmass the size of all of Myanmar is not trivial geopolitically, etc, etc, etc, Berlin Wall But Worse, What A Mess. I think I prefer keeping them in place and partitioning the country to this one. And if I keep doing that kind of thing I'm going to run out of ocean.
Fifth obvious idea, sue for peace. Make some gesture that makes the point that I can make them stop if I have to and try and bring all sides to the negotiating table to get things done. This has failed many times before despite international pressure. These people hate each other. It's also the only idea on this list that even moderately respects these people's independent desires to do things or not. I hate this one less than most of the options on this list but it's still unlikely to work.
Sixth idea, do some form of negotiated partition of the country. They tried this one, it sort of happened but hasn't ended the fighting, but maybe if you put in fuckoff big mountain ranges that are easily defensible by small groups of people then maybe that fixes it. I hate this one less than just forcing it on everybody but it's still got that berlin wall factor.
Any obvious ideas I've missed here?