At this early stage in the life of a young tree your thoughts are best inclined towards making the tree viable in later life. Say you want to plant it out into an open location in a garden. If you let it grow vertically upwards it will eventually grow inconveniently tall for harvesting fruit. A better choice would be to have it produce four sideshoots (N,S,E,W) of equal strength so that the tree with all its fruit will be well balanced, reachable from the ground or a short ladder, and the side branches growing out high enough that you can get under the tree if necessary to do other work.
If you cut the tree now it will produce side shoots, but they will be low to the ground. Whether that is good or not depends on your vision for the future. If you cut it back by half you will have strong sideshoots but fewer of them to choose from for the framework of your tree. If you cut back by a third then the sideshoots will be higher but less vigorous than if you cut off a half.
Maybe even then the side branches will be too close to the ground, so you leave it alone for a year to allow it to go to twice the current height and then prune back. If you want to keep it small to grow in a pot then this changes everything - you need to prune now, but using the same principles. It comes down to what you want it to be in say three years, which then defines it in 30 years.
When you have decided what is most important, wait until the tree is growing well so that any wound created heals over quickly, and use clean tools to cut.
Since the vision is for a pot, prune it now by one third, encourage good shoots N,S,E,W, and remove the others that may emerge. As the tree grows, increase the size of the pot. As the side branches grow, keep them balanced in length and volume, growing outwards and upwards, leaving the centre open.