Tablets are definitely worth the money when it comes to drawing, especially if they can already draw with pencil/paper. Drawing with a mouse is not a fun experience, and much harder to learn than drawing on a tablet.

When it comes to brands, generally Wacom is seen as the best option, but this does come at a (significant) price. If price isn't an issue then I would definitely recommend a mid or high range Wacom tablet (generally the price correlates with size and materials), but their smallest tablets are much too small to be particularly useful IMO unless the person using it is very young.

If your price range is limited, I would definitely also recommend checking out the XP-Pen graphics tablets . When it comes to performance I would say that they feel as good to use as a Wacom tablet and have similar specs , but the build quality is slightly worse. I've got a XP-Pen Deco Pro tablet , and I must say that I like it very much. After a year of use I found the tracking and pressure sensitivity good in sketchbook and Photoshop.

Generally the main differentiation between tablets you should be looking at is the working surface area - larger tablets will be more expensive, but are harder to take on the go and it may be worth checking how much desk space your friend can allocate! There are tablets with monitors built in (e.g. Wacom Cintiq or xp-pen artist screen tablets), but these are generally very high-end and I wouldn't recommend buying these for a non-professional digital artist, especially for someone who's never used a tablet before.

Also, it might be worth checking out the iPad pro if that's applicable. For a drawing-only device I would recommend a graphics tablet over an iPad pro, but the portability, build quality, and extra features of the iPad (iOS) are definitely noteworthy. The drawing experience isn't as good as a graphics tablet though, and the buy-in is much more expensive.

Just as a side note, the tablet will work best in drawing software like Paint Tool SAI, Clip Studio Paint, Firealpaca/Krita (both free!), and Photoshop of course.