You could do a lot worse than copying interesting and hard fights.
5th is built around resource management. Hit dice and various abilities are tied to short and long rests. If you want combat to be a big part of your game it's intended to be making the players spend and exhaust resources over the course of several encounters.
I cant remember where i read it but the baseline difficulty may be something like 4 medium encounters +1 hard +1 easy averaging to 6 medium per "adventuring day".
You don't have to play it like that, you are invited to make rule changes as you wish and adjust the focus of your game and the difficulty of your encounters, but if long rests aren't split up by drains on you resources then the system behaves very differently, some classes do much better and groups will go into every combat "fully loaded" you can then be stuck as a DM picking combats that aren't really threatening with no real costs (medium/hard) or swingy encounters which can potentially 1 shot people (deadly).
Acquisitions Incorporated is a great example of a game that is not about combat but I would argue that the one shot nature of sessions forces it to be that way.