To question 1. We have been without our kitchen for a while and will be without it for some time (due to doing all of the work ourselves, while working full time). Most of our meals are also homemade.
We were fortunate to have another space in the house with outlets on 3 different circuits and a wet bar sink. When we gutted the kitchen we relocated a portion of the counter to this room to function as our "refugee kitchen." On the electrical circuits, circuit one powers the refrigerator, circuit 2 is the small appliance circuit (single burner induction hot plate, microwave, and toaster oven. BUT, only one can be used at any given time or the breaker will trip), and circuit 3 is limited to the coffee pot due to other items on the circuit and outlet placement.
We have other small cooking appliance, such as sous vide, insta-pot, and crock pot; for these food can be prepped in our repurposed space and carried to a different location in the house to place then on a different circuit.
All in all it is quite manageable, the reduced number of burners (4 down to 1) and the fact that only one small appliance at a time can operate mean that a little more thought has to go into planning meals and the cooking order of operation. Also, certain meals can take longer to complete due to these constraints.
A couple pointers.
1) Small cooking appliances are a god send. The small induction burner is especially great to keep cooking and they are inexpensive on CL. Also, Insta-pots can be your friend you can make some good to great meals in them using them first as a regular pot and then as a pressure cooker.
2) Plan on how you will wash dishes. We have a sizable "wet bar" sink which makes things easier, but going from using a dishwasher to hand washing everything is a big change.
3) During the summer if you already have a grill consider using it more, both as a grill and to cook foil packet meals.
4) Start now, find some easy to make recipes and try them out. Get a few that you like and can easily make it whatever makeshift kitchen you are planning.