Help 😩

I’m a FTM so I’m so unsure of everything and just need some advice, or maybe we’re doing everything on track idk.. but my son will be 8 months the end of June, and I feel like he’s behind on eating food and it’s my fault.. I EBF and I’m a SAHM, so nursing is just my go to to feed him. I give him purees for lunch and dinner, and sometimes mash up an avocado or banana, etc; but it’s mostly purees. He won’t feed himself and has no interest in even touching food I put in front of him. He’s a good eater but he wants me to feed it to him. I see all these posts of babies eating everything their parents are eating and I’m like how do you encourage them to do that? Also, since we BF and don’t use bottles very often, I can’t get him to try sippy cups.. I have a 360 and a sippy/ bottle combo cup but he refuses to even give either a try. My questions are:

-am I feeding him enough food? What are good finger foods to start with?

-how do I start him on sippy cups/ what do I put in it? breast milk? Water?

(He is in the 98% for height and weight so I know he’s getting enough, just not sure of food to breast milk ratio?)