Hi and Welcome to Talk Parrots.
Where are you getting your conure from? A breeder? A breeder will tell you what they feed their chicks and it should be a good diet as most breeders usually do the best for their chicks and birds they may even give you some food to take home so your bird can continue its regular diet as you start buying new foods and introducing new food to it.
If you get a bird from a pet shop you will have to find out what they are feed it and then gradually change the diet especially if its only a seed diet.
Conures can have seeds and pellets and fresh chop, you can leave seeds in the cage all day however I only offer pellets as a treat once a day and never leave the dish in the cage all day or night. I am not convinced pellets are a primary source of a healthy diet for any bird.
I suggest you sprout your birds seeds and give him this daily as its healthy. Sprouted seeds don't have fat in them which will keep your bird from getting fatty liver disease.
Chop is made from a bunch of fresh veggies and some fruits. Most people who make chop for their birds usually buy organic veg and fruit to assure a healthy diet without pesticides. They make a large bowl of chop and freeze it in an ice cube tray and take out what they need to thaw on a daily basis for the bird.
There are a few threads here with lots of recipes how to make chop, sprout seeds and make birdy muffins etc. You can freeze any of these foods so you can offer an variety of interesting things for your bird to eat daily. You can leave the chop in a dish in the cage for an hour or more a day but if its really hot in the house the chop or fresh food can spoil or attract fruit fly's so remove it after an hour and discard it. Feed the bird chop 3 times a day if you like, you are only offering a small dish of it about the amount of a shot glass or 4 heaping table spoons of the mixture. They won't eat all of it.
You can also sit with the bird when you are having some alone hands on time and eat a carrot or lettuce or apple and offer it to them. I know my birds have always liked to steal anything I am eating so I encouraged that when we had hands on time, as it helps the bird learn new foods and its trusting you when it sees you eating foods they have never tried before.
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