The answer to 'how to install electrical panel' is to hire a licensed and experienced electrician to install a new electrical panel. Installing an electrical panel is a complex and potentially dangerous task that requires specialized knowledge and tools. Attempting to install an electrical panel without proper training and certification can be extremely hazardous and is not recommended for most homeowners.
A professional electrician will be able to properly size the new electrical panel to meet the power needs of your home, ensure it is up to code, and install it safely. They will also be able to handle any necessary electrical work, such as running new wiring or upgrading the service entrance. Attempting to do this work yourself can lead to serious safety issues, fire hazards, and potential legal problems.