"What about size and knife type? What type of chef knife would be right for me?"
If you cook a lot or for a large family, consider a 210mm or 240mm gyuto (chef knife) for home use. Although many professional chefs use a larger knife, the truth is that unless you get a rack or stand, most standard-sized drawers won't accommodate a long knife. You will need at least one smaller utility knife; like a 160mm gyuto (small chef knife) or a 120mm petty (small utility knife). This is the minimum, more is just plain more fun!
If you are cooking for mostly 1 or 2 people, a good choice is a 210mm general purpose chef knife, a specialty knife that is either 160mm or 170mm, and a small utility knife for cutting a sandwich, tomato, or trimming some veges or meat. A great choice is a 170mm santoku, a 160mm small chef or both. Either will soon become your 'go to' knife! Huge sets, for most people, contain lots of knives that rarely get used and use up space in small kitchens. If you don't cook much or have a tiny apartment-sized kitchen, just go with the santoku and a 160mm small chef or 120mm utility. A 2-piece set is probably plenty.
Are you a vegetarian? Or, do you like to make salads and lots of dishes that contain veges? If you are moving between cutting meat and salad veges, you should avoid cross-contamination by having a cutting board for meat and one for veg. In addition, you should have the right knife for the job. Have your handy 210 or 240mm gyuto for the meat and a santoku or nakiri for the salad sitting out and ready for action.
Here are a few suggestions. For cutting a variety of veges, choose either a nakiri or a santoku. Here's that santoku word again. It is such a handy tool to have! (I have both, but who's counting). The word literally means "knife of three virtues" because it is so good for vegetables, meat or fish. They usually come in 6 or 7 inch blades, so really great when you are cutting up a selection of fresh veg for soups, casseroles, stews, etc. Also, great for salads and slicing tomatoes. I find I use either my 160mm small chef or 170mm santoku exclusively when I want to slice a tomato, cucumber or anything else real thin! I'm no pro, but do have over 50 years of nearly-nightly home cooking under my belt.
Notice in the photos below that both a santoku and a nakiri have a wider blade. This allows for easy cutting and less sticking when cutting soft vegetables. Neither is particularly well suited to a big thick squash or pumpkin however. Use your gyuto for that.
More to follow. Hope you are finding this fun. I'm starting to get too long again, so check back for part 3 in a couple days!