How old is the tree?

If its a young tree and those are really the only 3 branches and they all meet the trunk at the same place I would probably lop it off below that point removing 1, 2, and 3.

That should cause buds lower on the trunk to break and grow new branches. You can then choose your new main branches from those new ones that form.

Assuming this tree is only one or two years old, I would cut 2 and 3 back to about the size of 1, making sure I'm leaving at least 3 nodes for each branch to sprout from. I would not prune 1 at all.
When 2 and 3 sprout out next spring, you may want to do some light summer pruning, just nipping back the longest branches, to encourage more branching.

Interesting, Hawthorne is in the rose family like apples pears peaches and plums.

You want to start to establish upright form by pruning before bud growth in the spring. Head back 3 to promote branching. Prune 2 an inch from the base. Train a new upright dominant leader from 2 base. Head back new leader after 24" growth to promote branching. When 1 starts to grow too long head it back as well.

Here is a link that might be useful: Hawthorne Tree

Thank you all!