Q.lavender tree
lavender tree is in pots but no new grow this year what do you do to get new growth

How did you provide winter care for your Lavender?
Is the Lavender that you have appropriate to your growing zone?
It's possible your plant did not survive winter.
Check the branches, do the snap or bend. Branches that snap off have died.
Look for growth down low at the root base; if the roots are still alive, this is where you will see new growth.
These links have information on the care of Lavender plants.
https://www.gardeningknowhow.com/edible/herbs/lavender/growing-lavender-in-pots.htm
https://www.gardeningknowhow.com/edible/herbs/lavender/lavender-in-the-garden-information-and-growing-lavender-tips.htm