Buy and Sell Tax - WTH??

I am still noob level in this game. Yesterday I heard about the term/concept of "Sell Tax". I was exposed to the concept while watching how to create a meme token on YouTube. Then looking around more I came across Buy Tax; mind blown!!

Now I am a bit intrigued.

So looking through the coins I have; I found one with a Sell Tax of 2.5%, PIKAMOON (PIKA).

Now even more intrigued which brings me here today.

Since PIKA has only been on the exchanges for a few weeks, I wanted to see how much they would have made from all the sell volume since launch.

This brings me here today with questions.

1. Is there a free data source I can pull from? The few I have looked at so far, Birdseye, CMC, CoinGecko, all charge for historic data.
   1. If anyone can help me pull the data for PIKAMOON (PIKA) that would be sweet. Since this is more of a curiosity for me, I can justify spending $45 on a monthly subscription to the pro tools.
2. Is my thinking correct that 2.5% of each sale goes back to the coin creators? Or is there more to it than just that?
3. I am surprised I haven't seen or heard about this in any of the other channels. Is Sell and Buy Tax not common?

Over the last couple of years I have just bought and held. I have never experienced buy or sell tax first hand yet, other than the price of gas that is.