Hi I am a newbie and I am planning to invest ETH coin but I only have limited amount of money to start investing. Can I buy less than 1 ETH?Your response are greatly appreciated.Thank you. 
Yes of course! You can buy fraction of Eth (i.e. less than 1 Eth).
And if you're buying from an exchange, you can definitely use any of the available payment methods listed there (including FIAT or regular currency like USD, Euro...) & if you hold any other crypto currency (BTC or others); you can always use sites (like shapeshift) to exchange it for Eth