Getting started with Substreams is very easy! Depending on the blockchain that you want to use, the best way to get started might change:
If you want to extract data from Solana, you can take a look at the Tutorials section, which covers the development of several useful Substreams (SPL tokens, NFT trades, DEX trades...). The Substreams for Solana Developers section is really useful if this is your first time using Substreams.
The Substreams Explorer teaches you to most basic extractions you can perform on Solana. More tooling will be developed for Solana soon.
If you have a specific smart contract that you want to extract data from, the substreams init initializes a Substreams project that extract the events from the smart contract.

Tracking a Smart Contract

Initialize a Substreams project

Tracking a Factory Smart Contract (Dynamic Datasource)

The substreams init command also offers you the possibility to easily track a factory smart contract (in Substreams terminology, a dynamic datasource). The following video covers how easy it is to get started with factory contracts on Substreams.
Initialize a Substreams project