Baking – Should the oven temperature be the same for smaller batch

The ham should rest for at least 15 minutes after cooking, and probably longer than that. So you could put the potatoes into the oven when the ham has 20 or 25 minutes remaining, and then when you take the ham out, increase the temperature to 350-375F and continue cooking the potatoes while the ham rests for 15-20 minutes.

There are some previous questions with good answers like this one, or this that go into much more detail than I'm about to.

You said your bread didn't rise with the first rise, if you don't have a first rise you can't go onto the next step. If your yeast was old, or the temperature was cold in your kitchen or you used cold water in the dough, or the yeast came in contact with salt then its action could have been slowed down drastically and it would take much longer to get a rise. I've had a first rise take up to 4 hours in the past because of these factors. The times given in recipes are just guidelines, you have to be result-driven. Active dry yeast also takes longer than quick yeast to activate. When using active dry instead of quick yeast you would get better results by mixing it with the water before mixing in. I'd recommend using quick yeast as it's milled into smaller grains and you can mix it directly into the flour.

Of course your yeast may have simply been dead, or killed by salt or heat. Get some good fresh yeast and store it in the fridge to keep it fresh long-term.

Also, using all whole wheat flour isn't going to produce anything like a baguette. Whole wheat flour is very heavy compared to white flour and will take longer to rise. A half and half mix would work better. I'd recommend sticking to the recipe first, then gradually modifying it over time until you get your desired result.