If you're a solo gardener and would like to plant some fruit trees, here is some advice that should serve you well.
Opt for bare root fruit trees
In this situation, you should opt for bare root fruit trees. These are fruit trees that are not sold in pots filled with soil but are instead sold pot-free, with their roots exposed. In your situation, you may find these a lot easier to work with than their potted counterparts. The reason for this is that bare root fruit trees weigh significantly less than ones that are placed in heavy pots and whose roots are surrounded by dense, weighty soil. As such, you should find them fairly easy to carry and to place in the soil on your own.
This is important because if you purchase trees that are too hefty for you to lift or to hold in place, you could injure your back or fall over whilst planting them, or you may end up planting them at an angle (because you lack the strength to hold them straight), which may result in these trees becoming unstable as they grow.
If you get bare root trees, you should find that (provided you are reasonably fit) you should be able to carry them to the planting spot in your garden and to hold each trunk in place so that it's perpendicular to the ground as you're planting it, without much difficulty.
Consider how you'll collect the fruit
If you're purchasing fruit trees rather than ones that don't produce fruit, then it is probably safe to assume that you are doing this because you'd like to eat, sell or give away the fruit that they'll produce. If this is the case, you'll need to consider how, as a solo gardener, you will go about collecting this fruit. If you'll be planting multiple fruit trees, then you may need to pick up kilos upon kilos of fruit during certain seasons, and this could be a challenge if you're on your own (especially if these trees are located some distance from your house).
In this situation, it might be sensible to purchase an extra-large wheelbarrow that you can use for the collection of this fruit. Even if the wheelbarrow has a generous capacity and you fill it with as much fruit as it can hold, you should be able to easily transport it across your property without much physical effort or any serious risk of injuring your back.
Contact a local bare root fruit tree nursery to learn about your options.