herbs are always great for my household and so simple to plant and maintain.
Alternatively, the packet of seeds should have planting seasons on the other side of them, follow their guide for best results. There are always others you can do indoors with water such as celery and avocado

I plant what we can use with our dinner and it is just wonderful watching them bloom!

We have tried various different vegies and fruits, I found I have had the best luck with tomatoes and strawberries.

Zucchini is very easy to grow and you can get a bumper crop. Silverbeet is also very easy.
Kids live picking tomatoes (cherry ones in particular) snow peas are also easy to grow and super tasty eaten straight off the bush

Depending on how much space you have, select just a few things to grow, but plant lots of them. That way if a few die you’ll have plenty of backups but also so you get enough produce to do something with, even if it’s just enough for dinner one night. We have had great success with snow peas and beans, and my littles love picking and eating them straight from the vine. Carrots are also fun and great to eat straight from the ground. Strawberries in spring (you can grow these in hanging baskets). Cherry tomatoes are easier to grow than regular tomatoes, but you’ll have to wait for summer again. A bit of trial and error and you’ll find the things that work well in your garden. Good luck!

I’d go with herb plants. Rosemary, bay leaves, oregano, parsley, sage… they all grow easily and quick. Other great choices are, in my idea, leeks and spring onions.