Welcome to R2R and your new addiction! We are all here to help. To echo some above an 8 gallon isn't really hard so much as forces discipline and schedule with limitations on what can be done.
You will almost guarantee yourself success if you commit yourself to 2 gallon or so water changes a week. Just make sure you match salinity and temperature closely before you change the water to avoid large parameter shifts.
It sounds silly on a tank this small but I would do a smart micro auto top off unit to replace the water that evaporates. It will help avoid salinity swings when life gets busy and you forget to add fresh water for a day or 2.
The water changes will help your water quality more than a protein skimmer. For this size tank you will want to keep it simple.
Add enough rock/macro algae to give the fish you choose plenty of hiding places. It sounds crazy but the more hiding spots the more likely the fish are to come out.
Stocking wise 2 fish should be a maximum and best to add them a month ago apart or so after the tank cycles.
I would recommend a neon goby, firefish, rainford goby, or possum wrasse. All of these fish are jumpers so make sure you have a tight lid.
A couple of shrimp should be no problem, fire or cleaner, then a few snails 1 or 2 of each kind only, aestrea, trochus, cerith.
Be careful feeding, you don't want to starve your fish, but once a day with the species above is plenty and no more than they eat in a few minutes.
As for corals try some gsp, zenia, colorful mushrooms and zooanthids. If you decide you want something more advanced you can easily reset your aquascape.