In an ideal world, you would have covered cropped in the Fall.
If you did this, you want to till or chop in the “green manure” in the cover crop in February before it goes to seed.
If you did not, then you can still add in compost. Depending on your soil type, tilling it in may be necessary or not. If you have heavy clay soil, the compost helps create air pockets, so it is good to till in. If you already have decent soil, you can top dress and let it get worked in over the coming year.
It is also good to test the pH of your soil. An ideal pH for a veggie garden is 6.0-6.5. If your pH is less than this, then it is good to use dolomite/agricultural lime, available at most garden stores (you can grab from us at Farmers Markets in March).