Hi Tom. Welcome to the Village. We're glad you joined us.
It really depends on the thickness of the wood you're working with. If you're working between 1/8" to 1/2", my go-to blade is the #3 scroll reverse. Its a flat blade that has good control, but can get into tight details pretty easy. If you have large sweeping curves or straight lines, a larger blade (#5 scroll reverse) works better as id doesn't wander as much. But detail cutting is much more difficult. If you have very fine details, 2/0 scroll reverse is great. Since its such a small blade, it does get a bit squirrely to control. But the tight detail work, its amazing.
You can also consider a spiral blade. This allows you to cut in all directions. It can be difficult to control on straight lines. I typically use spiral blades on portrait style cutting with a lot of organic/wavy lines. The kerf is much larger on these blades. I typically use a #3 scroll reverse spiral and a #1 scroll reverse spiral. I use Flying Dutchman from Mike's Workshop. He has a sampler pack as well that might be worth looking into. I'd definitely mail-order your blades. The stuff they sell at the hardware store are overpriced and garbage. Stick to the name brands: Flying Dutchman, Pegas, and Olson and you'll do great.
Clear packing tape is usually applied to the top of the pattern. It adds extra support to the pattern and prevents it from ripping.
I wouldn't put packing tape directly on the wood. Its difficult to remove and may leave behind a residue. Many folks will put blue painter's tape on the wood before applying the pattern. This is specifically designed to be removed from a surface without damaging it.
Here's what I do. I put blue painter's tape on the wood. The use spray adhesive on the back of the pattern. Let it dry until its tacky like a post-it note. Then apply to the top of the blue painter's tape. Then I cover the pattern with clear packing tape. It works really well for me.
I hope this answers a few of your questions. If you have any more, we're more than happy to help. I look forward to seeing your first project. Welcome to the hobby!