Hi there!
When we started on real solids with my daughter she did the same exact things! I finally gave up on the Cheerios and Kix and got her the Gerber ones... I wish I could remember the name! They melted in her mouth since she would not chew them all the time or chew all the way when she did. It helped stopped the gagging and choking that we were battling with Cheerios. We also had to "show" her how to chew... we would chew with our mouths wide open so she would mimic us- I catch myself now 8 months later still doing this- but in public! lol
We also found her pushing around peaches, pears and apple slices... it turns out that she could not grab them to pick them up since they were slippery. We finally bought the plate that has a suction to the bottom to stick on the tray and it also has a lip on the plate/bowl to help her grab the foods easier- watch though that he does not put a whole handful of food in his mouth at one time though. It was also great when she start to use a spoon.
I almost forgot... we also started to buy the Gerber Dinners that look like tv dinners that come in a box. It is softer solid food but great to help teach chewing small pieces!
Good luck, I hope this helps you! Many blessings to you and yours!