Apologies if you know how to do any of these as I don't know your individual skill level or knowledge.
Breakfast: master eggs. This will take longer than a week but at least you can get started! Poached and scrambled would be my suggestion, and throw in a quiche or fritatta if you feel like it. If you're not into eggs, then try pancakes. Try a few different versions: crepes, american, fluffy whipped egg whites versions, ricotta cakes. It will help you master batters. Also try making your own granola, surprisingly simple, and flavor combos are endless.
For lunch and dinner, I would approach this more by technique.
Make a soup, but make your own stock. Bonus points if it's one where you make your own noodles or dumplings.
Make something braised where you use the pan juices as a sauce. Beef braised in red wine, beef bourgignon, coq au vin, something like that.
Make a stir fry with a sauce. Try to get a perfect chop and dice on the veggies. High heat, individual ingredients, learn the technique to velvet the meat.
Make a perfect steak. Come to room temo, seasom, sear, finish in oven, rest. Make a side that calls for blanching vegetables, so you practice doing that, too.
Roast a chicken, with all accompanying veggies in the same roasting pan. A one dish meal, all you need is bread and wine. Check out Thomas Kellers method.
Make a vegetarian salad that is hearty enough for vegetarians and meat eaters alike. Think grains, beans, etc. No iceberg here. Make your own dressing.
Make your own tomato sauce if you haven't before.
Make mac n cheese with homemade cheesr sauce. Alternatively, a croque madam.
Break down a whole chicken. Then make chicken saltimbocca.
Advanced mode:
Make eclairs. Learn choux dough, pastry cream, ganache.
Make homemade hum bao. Char siu, sweet yeast dough.
Make enchiladas with homemade tortillas and sauce and braised beef filling.
Make palak paneer. Make the paneer yourself.
Make mole. Godspeed.
Make homemade ravioli stuffed with homemade ricotta.
Make paella. Make your own stock. Devein your own shrimp.
Roast a whole stuffed fish.
Gordon Ramsay answer: beef Wellington.
Most importantly: have fun!