Studies have found unless you buy veggies directly from a Farmers Market, frozen from the supermarket does retain more nutrients and vitamins then buying it from the produce section. They are flashed frozen either the same day or the next from when they are harvested. Yes there are some fundamental differences in texture and color, such as parsley, basil, spinach, squash, celery and a few that I have missed, but that is freezing versus keeping fresh and you’re going to cook them anyway. A lot of the other answerers are correct on the how to’s, but I can’t imagine putting myself through all that hassle. There are staples I try to keep fresh on hand, celery (wrap in foil), onions, potatoes, carrots. I put them in the produce draws with paper towels on the bottom. They last longer than a month. Yes I did say potatoes, peeps I’m Irish, it doesn’t affect them. A little sweeter I know, but why is that wrong?
Parsley and Cilantro leaves may not be frozen with good results, but their stems can. I tie up the stems then freeze them. I just throw them in to whatever I am cooking still tied up. I also freeze chopped green bell peppers, not a fan but some dishes need it. When cooking frozen veggies, I find this works the best. Put into tempered glass bowl with micro proof lid. You can also use plastic wrap, it will vent itself. I like using clear glass so I can keep an eye on it without having to open up and take off the lid. Do not add water, just salt and sometimes a little sugar to brighten up the flavor. YES I said sugar, no responses please. Put in Microwave and cook for 3 mins, then shake about the bowl, return and cook another 3 to 6 mins. depending on the veggie. I try to slightly undercook them; by the time it makes the table they are perfectly done. Spinach the same way, then press out the extra water. You can tell they are cooked when you see a few tablespoon of water sitting on the bottom. I just drain it out.
Meat is easy too. Do Not use Zip Locks. Use really good plastic wrap, not the cheap kind, very important. Have you ever seen someone make tortilla sandwich wraps? They roll once, then pull it tight, then fold the side in and finish rolling it. Same principal here, roll once, pull it tight roll two more times. Then use the side of your hands to push out the air from the side and fold ends. Then roll the opposite way two more times pulling tight. You could then put in a zip lock to keep organized and it also helps buffer the food from the defrost cycle. Using this method, I never get freezer burn. I just pulled out pork chops I wrapped over 8 months ago, still looking perfect. Defrosting meat in the fridge works best, you don’t lose as many juices. There are other methods, but that is a subject for another day.