>>718570965
There are two starting points; Dream Land or Super Star.
Dream Land (Game Boy) plays a bit differently than most Kirby games since he can't copy abilities yet. It's a pretty short game that you can beat in 30 minutes. It's carried by its charming world and characters, great graphics, and incredible soundtrack (this is the norm for 99% of Kirby games). It is the first game in the series. It also has an unlockable hard mode that is one of the hardest experiences in the franchise funnily enough.
The second entry point is Kirby Super Star (Ultra) on the SNES or DS. This is where the standard Kirby formula was established. It's undoubtedly one of the best games on the SNES with fun bosses, lots of game modes (including a remake of Dream Land with abilities), minigames, and more. If you're curious about the differences between the SNES and DS, the DS has a few new game modes and minigames (minigames use the touch screen), redone cutscenes and graphics, and two enemies got redesigns (blackface and Twinbee knock off). Also couch co-op for SNES. DS is probably preferable but the SNES is still a classic.
The third entry point is Kirby's Adventure (NES, 3DS remaster, and GBA remake). 3DS version has no slowdown, fancier backgrounds, and 3D. GBA version has a new playable postgame mode and completely different art style and minigames that is a bit more polarizing. Neither is bad but I personally go with 3DS. Very fun and impressive game for the NES, I bring it up here because it might be disappointing to go to it after Super Star, when it's better to either start with this or play it after Dream Land.
Personally, I'd go with release order of
Dream Land > Adventure > Super Star
So you can see the progression of the series. Dream Land is only about 30 minutes and easy to beat, and Adventure is a great game with a lot to do.