I think Belgium is pretty much out of the question here. They will qualify for the next round 99% as they are always able to switch gears considering the overall quality of their squad. In most cases Croatia is also going to the next round in this group. Canada has had rather weak performances recently so I don't think they can just change gears and play on a totally different level. That's why it will eventually come down to whether or not Croatia is able to show a realistically positive performance or whether they might have a bad day or be unlucky against Canada. Morocco is a bit unknown to me, but I just noticed they had some strong performances in friendlies against Chile and Paraguay.
The favourite indeed belongs to Belgium and Croatia but in my opinion Morocco cannot be underestimate because some people thought the current squad is one of the best generation for Morocco team and at their squad Morocco have several players who played at big teams in europa such as Achraf Hakimi from PSG, Noussair Mazraoui from Bayern Munich and Chelsea player Hakim Ziyech so these players were familiar with European football style and with their experience i am sure they can bringing Morocco becomes an dark horses team who possibly can makes strong teams such as Belgium or Croatia slipped