If for some reason you need to add ssl certificate to your localhost project, you can do the following steps to achieve that.

Install and use mkcert #

# Install mkcert from Homebrew
brew install mkcert

# Create new local CA (Certificate Authority)
mkcert -install

# Create certificate for localhost
mkcert localhost

Install and use local-ssl-proxy #

# Use npm (or yarn, whatever) to install package
npm install -g local-ssl-proxy

# Start your local ssl proxy
local-ssl-proxy --source 3010 --target 3000 --cert localhost.pem --key localhost-key.pem

This will proxy all requests in your project through https://localhost:3010.