My kid is at the same stage. Right now he loves knocking down stacked cup towers, so we play a game of I try to stack the tower before he crawls over to knock it down.

I take a clothes peg and clip it on a leaf in the garden. Then carry baby about 5m away and turn back to the peg. Zigzag walk back towards the peg, while prompting "where is it?" When she sees the peg and smiles, we move in close and she grabs it off the leaf. Repeat on a different tree.

It's called The Peg Game :^)

I like to play a game I call toddler fetch. You throw a ball, and then they go fetch it and bring it back to you, and then you throw it again. You can use a soft inside ball to do that.

Another game I like to play involves them running back and forth across your field of vision, and you have a ball, and your goal is to hit them as they run back-and-forth. This is usually a soft ball, and an indoor activity, and you need to be intentionally bad at hitting them because the whole point is to get them to run back-and-forth and get tired. I play this particular game while sitting down, when I'm tired myself.

As a non-verbal crawler, they can still do a version of toddler fetch which is more like crawler fetch. Since they are crawling they will have to dribble - think soccer - the ball back to you instead of simply bringing it as would happen in toddler fetch. While you can explain the rules, it does help to just simply get excited when they bring the ball back and they figure that out really fast.