At this point whether they eat it or not, not really a worry. It's to taste new flavours, textures and to play with it also. With BLW the amount they actually eat isn't a lot at 6 months and you will get meals they just don't eat. My daughters nearly 1 and she will only now est broccoli if it's not pureed. Before it had to be pureed. Try to model eating and try not to stress at 6 months it's not about it being part of their diet as such. Milk is their source of nutrition still
Keep sitting them at the table and eating with them, you can sit them on your lap and let them eat from your plate too. It’s all about exploring tastes and textures so I wouldn’t worry if it seems like no food has gone in. Sometimes it takes something different to get them interested- try a lemon quarter!
Make sure he’s watching you and try modeling eating each item before you place it in front of him! He won’t actually “eat” any of it for a while but if you can show him that it goes in your mouth, then he will try and be able to start exploring more. And if he still has no interest then just wait a couple more weeks or so!