Hi , I am new in this blockchain field.. sorry for my ignorance

Try to learn step by step , how Blockchain actually works ..

so One word I found GAS ,, and after google it got this :

Gas is the name for the execution fee that senders of transactions need to pay for every operation made on an Ethereum blockchain,


Can anyone here please elaborate this for me with an example..

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For exapmple:  If I want to purchase ERC20 token, I have to pay GAS [ or excution fees]

Please help me.

Cheers