This is by no means a comprehensive list, but here is a brain dump

Get started with:

- https://github.com/ethereumbook/ethereumbook

- https://docs.soliditylang.org/

- https://cryptozombies.io/en/course/

- Join crypto twitter. A lot of projects have twitters that you can use to keep up on with what's happening.

- Join discords. A lot of projects have discords that you can use to keep up on with what's happening.

- https://www.youtube.com/c/Finematics/videos

IDE and Basic Tooling

- https://hardhat.org/getting-started/ (dev environment)

- https://trufflesuite.com/ (dev environment)

- https://docs.ethers.io/v5/ (web3 tooling)

- https://openzeppelin.com/contracts/ (security)

Node Infra

- https://www.alchemy.com/

- https://infura.io/

- https://moralis.io/

Indexing and Analytics

- https://dune.xyz/home

- https://thegraph.com/en/

- there's more

Wallets:

- https://metamask.io/

- https://gnosis-safe.io/ (contract wallet / multisig capabilities)

- https://rainbow.me/

- https://www.coinbase.com/wallet

Monitoring, Alerting, Simulating

- https://etherscan.io/, bscscan, polygonscan, snowtrace, etc

- https://tenderly.co/

Security and Audit - Trail of Bits Tools: Slither (static analyzer), Echidna (fuzzing), Manticore (symbolic execution)

- ConsenSys Diligence and their tools

- there's more

Oracles

- https://chain.link/

- there's more but I'm lazy

Bridging:

- there's a lot here

- https://docs.google.com/spreadsheets/d/1jYZOfU2R3PdzRmnY9Nfc...

Governance and Voting:

- https://snapshot.org/

Other things you may find interesting

- https://uniswap.org/

- https://curve.fi/

- https://app.1inch.io/

- Networks: Polygon, Binance Smart Chain, Avalanche, Arbitrum, etc

- https://ipfs.io/