At 4 months i started my son on cereal. At 6 months he was eating stage 1 foods, mostly fruits and veggies to start. Then the other stage 1 mixed foods. Then around 9 months i started him on stage 3 foods.
So at 6 months this was pretty much his schedule, a table spoon of cereal with formula mixed in to your consistency and a 6oz bottle of formula or a 1/2 jar of fruit. Then in between breakfast and lunch he would get a juice bottle if he needed or wanted a bottle. Lunch time he got the other 1/2 of the jar of fruit or he would get a 1/2 jar of a veggie and juice. Then around nap time he would get another formula bottle. Then dinner he got a whole jar of whatever and 1/2 of fruit for dessert. There were times he didn't eat it all but then i would save it for the following day. Then at bedtime he would get a 6oz bottle of formula but then be up around 3am for another one. You just have to see what your son will eat. But make a schedule. Breakfast, lunch and dinner.
My son now won't really eat breakfast, he eats a couple puffs (those snacks that melt in their mouths) in the morning with juice. Around 10am he takes a 6oz formula bottle for a nap. Then for lunch he eats a 1/2 jar of stage 3 foods with juice. Then some more puffs for snack with juice in a cup. Then dinner usually a 1/2 jar of stage 3 (i.e spaghetti dinner, veg. beef etc..) with cup of juice and some of whatever we are eating (if he is able to) to get him used to chewing our foods.
Oh and when you start feeding them jarred food remember when they don't want anymore they will let you know. They will either turn their head away from it or like my son try to hit the spoon or he now spits it out LOL! Well it's funny but messy! Good luck