Here's an explanation about the classification of Blockchain according to Layers:

check it out on Binance Academy‼️

Link: https://academy.binance.com/en/articles/what-is-layer-0-in-blockchain?ref=AZTKZ9XS&utm_source=BinanceTwitter&utm_medium=GlobalSocial&utm_campaign=GlobalSocial

Understanding the Layers of Blockchain will help you further understand what projects are better for you to invest & HODL