New step by step token with BNB earn functions on Remix and solidity 0.8

i want to create a new token step by step and need some instructions and tips from the professional developer. i think best is to start as ERC20 on remix with solidity 0.8.0 or higher

Questions:
first of all it is possible to change an token after creating and sending it to bscscan or etherscan?
if a create an ERC777 token it is possible to use it on BSC BEP20 network? (to swap it in DApps like PancakeSwap)
than if i create an ERC20 or ERC777 token is it possible to connect it to an ERC721 token later?
which network do you prefer for that is cheap and can understand for beginners? (i think BEP20 because is cheap and most understand it, ERC20 has very high tax fee and beginners with small money maybe loose many of it, TRC20 is also cheap but not easy to understand).

what i have learned until now
unfortunately i am at the begining with solidity and only have knowledge of webdesign like css /scss /jquery /a little big php and i also dont speak the best english. i have read a lot of sourcecodes and also tried to connect to remix and to deploy but only the basic source codes works.

for the beginning of this step by step way
i have now this sourcecode:

// contracts/GLDToken.sol
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";

contract GLDToken is ERC20 {
    constructor(uint256 initialSupply) ERC20("Gold", "GLD") {
        _mint(msg.sender, initialSupply);
    }
}

Questions for the beginning of coding:
what functions i need for reflect to holders and get % from the tax to 3 different contracts? and what fuction to have access to the sourcecode example to my sourcecode on bscscan?

the features:
multipurpose function: if holders have some coins of this token that they can later use it to buy and sell nfts with the same currency (this token)
reflecting tax fees: holders get some tax fee back with an start and end limit for example only if they hold 100 coins and maximum 1billion coins.
whale / chart fluctuation protection: a function that if someone with a big amount of coins will sale them that he must pay higher fee and that the holders also get more coins back
multiple contracts: i want a function that from the fee directly some % in bnb (smart chain) goes to the right section / contract for example developer / charity / liquidity to hold the token clean from problems, like if i use all amount for charity that not the coin goes down.
bnb earn function for coin holder: i want that the holders got some % in bnb and some in the coin currency because of the event the coin goes down that they earn benefits and to make the coin attractive.
auto burn function:
30% coins lock at beginning with auto burn function: from the remaining coins every one week 1% get burned and if no coins remaining 1% of the locked coins will burned.

and now why i need to change source code later:
i want at the point the owner have earned enogh coins that the tax fee split only to the charity / liquidity and reflecting to coin holders. and also if i create an nft marketplace that i can connect it to this token.

You should look over the guide at OpenZeppelin Upgrades: Step by Step Tutorial for Hardhat

This will get you started with a proxy, which allows updates to your token.

You will need to figure out how to link different tokens to each other. You can follow some tutorials on how to have one smart contract call or interact with another.
https://www.zupzup.org/smart-contract-interaction/

unfortunately i am at the begining with solidity
Then for sure go over the tutorial. It will get you a dev environment.

what functions i need for reflect to holders and get % from the tax to 3 different contracts? and what fuction to have access to the sourcecode example to my sourcecode on bscscan?

Take a look at the many safemoon forks and understand how their code works.

unfortunately i dont understand the tutorial because of language problems

Start with cryptozombies to learn solidity. For reflective fees, check reflective finance or safemoon source.