I have chain built using
substrate-node-template. Now what are the steps to connect my chain to Rococo test network?
If you have build a chain using the
substrate-node-template you have a solo chain, you have to integrate Cumulus to convert your Substrate FRAME runtime into a Parachain runtime.
There is a tutorial on the Substrate docs about it: Convert a solo chain, personally is not my favourite tutorial there, is worth reading to understand the theory but not very practical.
If you are in a early stage I suggest you to start with the Substrate Cumulus Parachain Template.
This project is originally a fork of the Substrate Node Template modified to include dependencies required for registering this node as a parathread or parachain to a relay chain.
Or you can use it as a reference to check what you need to add into your chain, another good resource is the Cumulus Overview.
The community shared more resources before in this StackExchange question: What is the best tutorial to convert a substrate-based standalone chain to a parachain?
Deploy on Rococo
Once you have your parachain, there is a tutorial in the Substrate Docs that demonstrates how you can deploy a parachain on the Rococo test network: Acquire a testnet slot.
To update some things, you can get ROC tokens using the new Polkadot Faucet instead of the element channel.
And when you have everything ready open a request here to get your slot on the Rococo chain.