I created a geth Full Node. Through this I created a new account and a Keystore file was created. Can I import this Keystore file to Metamask so that I can transfer funds?
Yes you can add your account to your metamask. In order to do that, open your metamask, then click on your account picture (on the top right), then click on the "import account". In that place you can select the import method to JSON file, then upload your keystore JSON file there. For more information you can visit this article