Hi Komeil! Welcome to Open Zeppelin.
Looking at your code
IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x10ED43C718714eb63d5aA57B78B54704E256024E);
Which network are you deploying to? If you are deploying to a test net, this router address needs to change. The router doesn't exist anywhere, but on BSC's live net.
As you mentioned you are new, I highly recommend doing this tutorial.
You don't have to understand it 100%, but it's a great way to get you up to speed and get a developer environment going.
After that check out
I know it's a pain to go through all this, but as you learn you will give yourself the skills needed to create any type of smart contract you want.