Start with downloading and installing the SFDMU plugin:https://github.com/forcedotcom/SFDX-Data-Move-Utility
The following data will be migrated between the target-org and the source-org when using the export.json here on the right. You first need to unzip the data.zip file which give you a folder to perform the actions.
Perform the following steps to migrate this data between orgs
Install the Salesforce CLI by following the steps mentioned here: https://developer.salesforce.com/docs/atlas.en-us.sfdx_setup.meta/sfdx_setup/sfdx_setup_intro.htm
Authorise the source-org (so the org where the data is currently is with the help of the the
sf org login webcommand) https://developer.salesforce.com/docs/atlas.en-us.sfdx_cli_reference.meta/sfdx_cli_reference/cli_reference_org_commands_unified.htm#cli_reference_org_login_web_unified
Authorise the target-org (so the org where the data should be going)
Install the SFDMU plugin by running
sfdx plugins:install sfdmuin a terminal
Make sure to create two Custom Settings to disable two Triggers on Resource and Resource Type as described here
Download and navigate to the export.json
Navigate your Terminal to the folder where the export.json is stored
Run the following command, replace the usernames of the target and the source with the usernames you used to authorise the orgs in step 2 and 3.
sfdx sfdmu:run --sourceusername <SOURCE_USERNAME> --targetusername <TARGET_USERNAME>