Q.dwarf orange tree
I have had dwarf orange trees 4 yrs, two in a pot and two in the ground. One grows great, about 7′ tall, bushy and green but has no buds (flowers), thus no fruit. I have heard of manually pollinating it but how if no buds?

Here are some articles that will help you pinpoint the issues.
https://www.gardeningknowhow.com/edible/fruits/oranges/orange-tree-container-care.htm
https://www.gardeningknowhow.com/edible/fruits/oranges/no-fruit-on-orange-trees.htm
https://www.gardeningknowhow.com/edible/fruits/oranges/hand-pollinating-oranges.htm