Lots of the above suggestions are great! A thing or two to think about regarding Mixcraft - Sonar owners can get the full Pro Studio for $99, only $10 more than Recording Studio.
https://www.acoustica.com...xcraft-pro-studio.htmlAnd, if he wants to do any singing on the songs he creates, he'll eventually want Melodyne Essential. Which comes included with Mixcraft.
My usual take on this sort of thing is to start somebody off on something free or REALLY cheap, in case they don't stick with it. But there are some time windows closing on great deals right now.
Also, if you go for the Focusrite Solo, as Martin suggested, BH has a promo going where you also get a free license for Addictive Drums and one ADPak as a 'rebate'. Probably best for general-use one is the Fairfax 1 or Fairfax 2. IMHO.
Also, the Solo comes with a lot of other plugs which don't suck, including a license for any one of his choice of XLN's Addictive Keys.
www.bhphotovideo.com/c/product/1251661-REG/focusrite_scarlett_solo_2nd_gen_scarlett_solo_usb_audio.html
If he gets past these, the GAS will probably have bloomed by then, and it'll be an entirely different set of suggestions.