Getting our young children to brush their teeth is quite difficult! It will take years to get them to brush independently so don't give up so easily.
When our daughter was still a baby, we would let her watch my wife and I brush our teeth.
The first time she actually put a toothbrush in her mouth was when she was 9 months old with 2 baby teeth that had come through. She is two and a half now.
We use childrens' toothpaste that contains fluoride. It contains half the concentration of fluoride compared to adults toothpaste. There is no need to place much toothpaste on the brush and a small smear is enough. After nearly 2 years, we still haven't finished the original tube of toothpaste!
Be careful about using too much toothpaste because at such a young age, children will swallow the toothpaste. Swallowing too much toothpaste will affect the development of the permanent teeth, called fluorosis.
Playing songs may help encourage your child to brush their teeth.
A children's toothbrush is appropriate to use. They usually don't last very long because they like to chew on the brush.
It is appropriate to help with their brushing to ensure it is decently clean. You don't need to try to brush it immaculately at the expense of making them hate toothbrushing. I have heard of other people trying to floss their babies teeth! There is no harm in it and it would be good to start the habit earlier than later.
Rinsing after brushing is also something that you will need to teach. They will start off just drinking the water as they don't understand they need to spit it out. Eventually, your child will understand what to do. As we all have!
Even now, we are still working on getting my daughter to brush her teeth better and rinsing. She often spits all the water out onto herself!
Fortunately, tooth decay in such young children is uncommon. Diet is a much more important factor than toothbrushing.