I have a 5 1/2 mth old boy who is eating solids...

I have a 5 1/2 mth old boy who is eating solids, weetbix for breakfast, friut for lunch & veg for tea. Just wanted to know when you can introduce baby biscuits, like arnotts? I thought they needed teeth first, but looking back at photos of my daughter eating them before teeth. This is my 2nd child how quickly you forget.