Nice trees that should grow well for you in Florida. The Serissa and the Juniper can be grown outdoors year round. The Fukien tea and the Ficus will have to be indoor plants during the coldest part of the year.
All are good species for someone new to the hobby. These are all commercially mass produced plants, and as young plants don't have a lot of character, but really your selections look nice, pleasant to have around. I would not do any pruning this winter. In spring-summer you can work on all of these. For the mean time, just keep them healthy, learning the when to water, fertilize and the routine of basic care is important before you dive into pruning, wiring and styling a tree.
Some will recommend moving these out of bonsai pots and into large containers for growing out to get more character, don't do this until the locally appropriate time for repotting (I'm in Illinois, and don't have a feel for Florida horticulture) What is good timing for me, may be bad for you as we live about 900 miles apart.
However, you may just keep them as they are for a year or two, to enjoy. Then as you learn more about the design aspects of the hobby, down the road you will see the changes you want to make. But don't do anything until spring. Just keep them watered and in the sun.
Both the Serissa and the Fukien Tea will flower, and flowers are a sign of good health. See if you can get them growing well enough to get flowers, that will be the sign you are doing a good job and have the horticulture mastered.