the point of clear coat is that it can make the paint shiner and last longer, also u can wet sand it 2 almost or make it look like glass. theres many type of clear coat
WATER BASED ACRYLIC VARNISH
Water based varnishes are safe, durable, non yellowing, fast drying, have low-odor, and can be easily applied.
The main problem with water based finishes is the water in the varnish can raise the grain of your wood resulting in extra sanding for you.
Even so, waterbased varnishes are some of the best types of product to use on your wood work prior to baseboard installing, hanging those doors or throwing books onto a new unfinished shelf.
Another thing to keep in mind is, a waterbased varnish can be applied as a top coat over a latex painted surface, like a faux finish.
CLEAR EPOXY
Epoxy coatings are two part mixtures, making them the most durable, hard wearing finish you can apply.
I do not recommend epoxy, unless you have a good amount of paint and clear coat application experience.
Epoxys can be very difficult to use, they tend to yellow quickly, or cloud over and lose their sheen in a short period of time.
Epoxys should be applied by a professional painter or wood finisher.
LACQUER
Before the carpenters begin baseboard installing or hanging other types of wood trim and doors, I will first spray them with a lacquer finish.
Lacquer builds or layers well and the more coats applied, the greater durability, depth and shine it will have.
Lacquer is quick drying, somewhat water resistant, durable and beautiful looking.
As a disadvantage lacquer does take some practice to spray on and can be non-forgiving when it comes to sags or runs.
If you decide on lacquer as your coating of choice be sure to use a mask specificaly made for lacquer application.
Filtering of lacquer prior to application may also be required.
PLASTIC COAT
Plastic coat is one of the hardest surfaces you can apply to a surface.
Plastic coats are easy to use, fast drying and will not yellow over time.
Plastic coat can be expensive if you're doing a large job like baseboard installing or finishing doors and large furniture piece.
i hope this helps