RealGM

How is he progressing ? Which current NBA player he could be compared to?

you can Watch the Eurobasket U16 to have an idea of how his game is "maturing". So far, looks good.

Lot to be improved still, but hard to guess what comparison i can give as it's pretty clear he's far from having an adult body (and his frame looks pretty good).
Eurobasket U16
He would be playing at the wing in the nba, so i would guess Tatum would be the best possible comparison (body type included, and if he reaches this level). Depends how he will fill out, but if it's like for his dad (former pro bball player here), no reason to be worried.

Fiba channel

Getting in the train early. He looks like a men amongst boys. Very fluid for his size, good shooting form, agressive, knows when to do the extrapass...
Some highlights



There are so many moving blocks at the moment but he looks like a blue chip. He projects like a 4 who likes to hang out in the peremeter and with some playmaking chops (nothing like KG or Webber, more like a Siakam).
Regarding a comp, it's wayyyy to early and I will look like a fool in a few years but he's giving me Siakam/more defense-oriented Banchero.

Undersized for the position, he's dominant because he's physically stronger than the competition. I don't see anything special in his game.

Undersized ? at which position ? He's been measured at almost 6'9 (204 cm) barefoot in january with a 7'2 wingspan (217 cm). The most impressive is his 9'0 standing reach barefoot (274 cm). Here are the measurements : https://youngstargame.com/tableau.php?param=ant&lang=fr
He's really big for the forward positions, could even play at center given his 210 pounds frame at his age, he's only 16.
To me his main weakness is his shooting, he didn't improve last two seasons, and may be a lack of explosiveness.

He finished his Eurobasket U16 today, and France qualified for the WC U17 in Turkey next year. So barring injury, we will see how he finished the first stage of his career, before his pro career.
We finished 5th though, so he might be out of the 5 best players of the tournament (but i doubt they will forget him considering his impact and feel for the game). We will see after the finale between Lithuania and Serbia (also some nba potentials there, as expected).

For this tournament, he had amazing last two games, but overall, his skillset is really way above average. Lacks a bit of verticality (but he has a great wingspan and he uses it well) and hanging time, but he can still do - well - everything on the court without a lot of mistakes (his turnover rate is good considering the time he spends with the ball in his hands).
Hope he can bulk up a bit (his dad was built like a tank when he was a player) before next hoop summit - if he's eligible, not sure - so that we can have an idea abt what to expect before next U17

He plays bit like Cameron Boozer, isn't he? Less stronger and less developed back to back game though.