Picky toddler or not hungry? Help!

I think it's more fustrating making my tot something he loves and he doesn't eat it.

Today for lunch he had ham, yogurt pouch and some bread. He didn't like the ham all the sudden so I switched it out for toddler raviolis he loved when I put red sauce on them. He immediately spit it out. I gave him a PB&J; (something he never turns down) and he ate maybe 5 bites 😑 he finished his yogurt pack and milk. Had a few pieces of bread but that was it. He can usually eat much more than this. I cleaned him up and he was off playing. He's been asking for snacks all day, I gave him his usual at the usual time and afterwards it was a small piece here and there but definitely not enough to fill him before lunch, I even cut any snacks off an hour before lunch..we play this game pretty often.

So now I don't know what to do. Is he just not wanting to eat? Is he being picky? I took him almost and 40 mins to eat lunch today. I offered a few things he usually likes and he just ate a few bites. Should I just give him healthy snacks throughout the day when he doesn't eat much? I don't want him to develop a bad eating habits of constantly eating all day 😕