Fundamentally....yes you can grow a bonsai tree in a garden with the right soil, lighting, watering and pruning controls. The proper care of a bonsai tree is always needed. In a garden though there will be many new challenges. To be seen and appreciated a bonsai tree should be much higher...like on a stand...unless you're thinking this tree is just a small scale and you've called it a bonsai tree for description. I don't imagine you or your guests would want to crawl down on the ground in the garden to view the tree at eye level. Will it be a bonsai tree in the garden bed?....it will be a tree. Yes trees can be grown in a garden bed. A raised bed would be best for what I imagine you're thinking about. Read my note at the end regarding container gardens.
In a garden your tree would also compete with whatever is around it growing....and sharing a multitude of insects and potential problems. Keep that in mind.
While in the ground this bonsai tree is going to wildly grow and within a couple seasons probably no longer look like a bonsai tree. Once the tree is actually a bonsai tree....you'll want to restrict certain types of growth...that will be a challenge planted in the garden....but it is possible.
Climate. The tree you're planting in the garden would need to stay there....your profile doesn't say where you are located so climate conditions are unknown. You might want to add your location.
I have seen garden trees though, some pruned-smaller sized trees growing in garden areas to resemble bonsai trees. The trees will grow. They do look interesting in the right setting. But they do require regular maintenance. Trees don't just stay "small"...they grow.
Pines.....growth really needs to be contained. Pines suck up space and not everything grows well next to pines. Keep that in mind.
Okay...enough rambling....
If I were you....
I'd say...Google research - Container gardening. Apply some principles of containers to your garden bed. You can create multiple levels with containers and still have that garden space. This would probably facilitate more of a bonsai tree view as needed. T would be easier in the care category....but still regular work. You and your guests would better appreciate a well designed container garden. Gontainer gardening can also separate watering and fertilizing needs. A multi level garden is excellent in the right setting....and much more controlled. Containers also keep roots separated better. For what you're doing...thinking....that's what I'd be looking at. Search photo attached for starter.
My thoughts. What do you think?
