Not a joke: simply stop buying meat. Don’t think about how to ‘replace’ meat. Don’t attempt to limit yourself to a certain number of meat meals a week. I tried those things, and I completely failed at them. Make a list of all the meals you eat that do not include meat and/or can be made without meat and just make those. Make sure these are meals that you want to eat - donuts and cheese pizza are fine.

Random suggestions:

-Spaghetti - extra mushrooms, plus onions, peppers, spices as desired

-Veggie sandwhich - Bread of preference, cucumber, tomato, lettuce, humus

-Pizza. Yes, pizza.

-Tacos - black beans, roasted sweet potato cubes, pico de gallo, cheese etc

-Roasted cauliflower - cube it, toss with oil and spices, roast it.

-Chili - buncha beans (pinto, kidney, black, even garbanzos can work), tomato, onion, garlic, chile powder. If you wanna go nuts, add corn and, wierdly - barley. It works great.

-Chana masala - Google it, basically chickpeas with a gravy made of tomatoes, onions, garlic, buncha spices. Very similar to making chili.

EDIT: Formatting. Doh.