No - not even close. But that may not matter for you....
A suspension seatpost is one that has an internal spring/shock absorber. have an internal tube like a car's shock absorber, and others use a parallelogram of some sort.
When you get on the bike, the saddle will move down a bit, affecting your bike position and varying the saddle/BB length. Some
Some people minimise this by running the spring at high tension so it is rammed up against its stops all the time. This defeats the purpose, and still sags under increases in weight like bottoming out on a dip/landing.
By comparison, a full suspension bike will generally keep the saddle/BB height consistent, and also the rear axle/BB distance to minimise weird effects.
Why might it not matter? A road would have to be pretty harsh on vehicles to require a full suspension MTB. Sealed roads should be rideable by a road bike, and metalled/shingle roads only really need wider tyres to minimise sinking-in.
If you work on your technique, there's every chance a hard tail would work fine for you. Avoid smashing through/over potholes and obstacles, and even a fully-rigid bike would be rideable.