If you/your friend are new to all this, I would suggest that you stick to bitcoin, or at least to invest majority of money in it, especially until you figure something sout and how this market works. But even then, if you decide to invest in altcoins, name of the game should be "make as much BTC as possible".
Thing is, while altcoins might offer bigger returns in the short time period, being a newbie means that you won't sell that altcoin at the right time, greed will kick in no matter what you said to yourself before like "I will get out when it makes 3x) so in the end you will end up with less money than you would have if you just invested in bitcoin.
I would wait for a dip.
I know people that said the exactly the same thing when BTC went to 30k, and are still waiting for dip to buy BTC for the first time. Imho, better tactic is dollar cost average if someone ain't sure. Less hassle and you don't have to time the market.
Another solution is to do dollars cost average during a fall.