Sewing with Knits

I am so sorry, I know this is a ridiculous question, but, I have a Janome machine. Am I able to sew knits on a regular machine?  Do I need a special foot?  Any, and all, advice is greatly appreciated.  Thanks so much in advance.

I have a Janome too, and it's a champion with knits.  I just use a normal foot, though I know some people like a walking foot.  I've tried the walking foot, and I don't like how bulky it is, but that is my preference.

The kind of needle you use and the stitch you use is more important than the foot.  I've noticed that my machine is not a fan of ballpoint needles, though they are recommended for knits.  Universal needles will work well for any knit without spandex.  For knits with spandex, you'll want a 75/11 H-S stretch needle.   A stretch double needle will give you really nice hems too.

For stitching, use a zigzag stitch set at 0.5 width and 2.5 or 3.0 length.  You can use the same settings for hems, or just a normal straight stitch if your fabric has very little stretch.  The zigzag is better than the straight stitch because it has some stretch built into it as does the fabric, so when the seams stretch across your body they won't break.  Straight stitched seams can do just that.
Play around with scraps whenever you start a knit project--it'll help you figure out what works for that fabric.

On really nasty knits you can also use the stitch that's shaped like a lightning bolt.  It takes longer to stitch with this stitch, and it is an absolute last resort for me, but they're are some knits that refuse to be tamed elsewise.

Have fun, and don't give up.  Knits are initially a little frustrating, but the more you work with them, the more you'll like them.  /they make for such fast easy projects, and fitting them is more forgiving.

Thank you so much Elizabeth for your very thorough and helpful response. For small children there are so many cute knits for me to choose from, but I didn't want to waste a lot of money unless my machine could handle it.

I'm glad to be of help.