Don't ask these type of question, as most of the people will recommend you coins that they have bought.

If you have no clue, I think either you should spend some time to know some altcoins, best way would be to use coinmarketcap.com and check the coins with low market cap and good team, etc.

Or if you are adamant about just investing, then buy up some of the primary coins like Bitcoin, Eth, LTC, etc.

If you don't have time to spend to learn, then I would advice not to invest at all, as you will be walking blindly.