You can go through a number of different tutorials to sharpen your skills as a dApp (decentralized application) developer on the Concordium blockchain.
In Setup the developer enviroment you learn how to set up the development enviroment for working with smart contracts.
In the Counter tutorial, you are going to build a simple smart contract with a counter that can be increased or decreased and where only the owner can perform the operations.
In the piggy bank tutorial, you are going to build a simple smart contract modelling a piggy bank. It should allow any account to insert CCD and only the owner to smash it, taking all of the CCD inside.
In the wCCD tutorial, you are going to get familiar with the deployed wCCD token on testnet. You are going to write a basic web front-end example that can read from and write to the deployed wCCD smart contract on testnet.
In the Minting tutorials you will mint and transfer various types of tokens.
In the NFT marketplace tutorials you will setup an NFT marketplace.
In the eSealing tutorial, you are going to learn how to seal a document, so you can prove that it was in your possession at the time of sealing. You will use a front end and the Concordium Wallet for Web to register the file hash of a selected document in a smart contract and then display the timestamp and the sealer from an already time-stamped document at the front end.
Once you are familiar with smart contracts, it is a good idea to read the Smart contracts best practices.