Uuuuh, I guess it all depends in which direction you wanna interpret orc! I think a lot of orcs end up looking a bit... Shrek-ish because of the exaggerated proportions. In truth, most orcs are depicted with extremely square jaws and really pronounced underbites.
Here's a WoW orc, a BG3 orc, and Shrek- Who doesn't actually have any sort of tusks or underbite, but does still have a pretty exaggerated mouth size compared to the rest of the face. The sort of really short and wide nose (which makes a contrast with how much of the face is taken proportionally by the mouth) does also contribute to the look. Wide noses can be used, but some orcs tend to push the shape of them making the bridge length incredibly short, specially based on the other proportions in the face.
It's also kinda important to acknowledge that the way orcs have been drawn and depicted in many shows, games and such come from a uh, kinda... Racist caricature perspective, almost. They're one of those fantasy staples that kinda has a finnicky history
And like, you really don't need to base your orcs on the usual ways they've been depicted! No Shrek needed! You don't need to give orcs an underbite! That the magic of designing your character. Tusks can work perfectly fine with more human-proportioned jaw.
This is super messy, but if you have somewhat curved tusks, they can poke out of the lips without needing the underbite at all. There's a few artists who have done much better tutorials on this than I could- You may wanna check this one from @douradart !