I plant most things from seeds direct sown. The two exceptions are tomatoes and peppers.
As far as what things can stand cold temperatures, here is a list of cold tolerant plants:
Then these are resistant but not quite as much so as the others:
You can plant, but the seed will not germinate until the soil is warm enough. I think a lot of seed types will lay dormant in the ground and sprout when conditions are right. However some seeds, like corn, will rot if the conditions are not right when it is planted.
Check weather records and see if you can discover what is called "Average date of last spring frost".
I find that I can plant the early named veggies two or three weeks before that date. The beets, chard, and parsnips a week before that date. Corn on that date and squash and beans a week after that date. Cucumbers should not be planted until the chance of frost is past. Here I plant cukes on June 1.
Of course these guidelines may work most years, but our weather has no guarantee with it. I have seen frost here every month of the year except August.
We just have to take our shots when conditions are favorable, and hope.
Keep an eye on the weather forecast and be prepared to offer some protection to the plants if needed.