what is Gas Used by Transaction:
159,170 (100%)
is it wei, gwei or matic?

what is 100%

Gas is gas

Then in order to determine how much you need to pay you multiply gas used with base fee per gas

gas_price means wei per one item

Gas - means number of items

right?

gas is a unit

1 Gas = 1 Gas

what is 100%
major of my transaction has that thing about 5%

gas limit

is it good to have about 100%?

Not really. Perfect 100% util of gas usually happens when exec runs out of gas

low can I calculate optimal maxPriorityFeePerGas, maxFeePerGas

or gasPrice
?

From gas station

What are best faucets for Goerli eth?

do you know some? with free api

ethgasstation

You also have Infura

If you're using ether.js you can call it using const currentGasPrice = await provider.getGasPrice();

Where provider is const provider = new ethers.providers.getDefaultProvider(INFURA_HTTP_ENDPOINT);

And you get yours INFURA_HTTP_ENDPOINT once you create Infura account

i have

is it safe to use?

What do you mean by that?

so i will use it . thanks

can i do something like that with "gas" parameter? how big should it be

.buildTransaction({ 'gas' : 10**9})

You can only manipulate baseFeePerGas and gasLimit parameters

gasUsed is deterministic and it depends on your code and function that you called

It depends on your needs

ho cat I set them right?

not all of it set as 1*10^9 I dont feel it good idea

i need to mint nft)

about 2 hours for transaction is ok

If you need to add your transaction to next block asap than use something like gasPrice = last_block_gas_price * x, where x is anywhere between 1.2-2

If time is not that much of the concern just use last block gas price

https://etherscan.io/gastracker also shows you current gas prices