Yes, you can start your pool anytime after Week 1.
For our NFL Pick 'Em pools, you can do so by accessing your Commissioner Console and then Pool Settings. Next, click on Pick Settings and in the Pool Starting Week setting, you can select which week your pool will start.
For our NFL Survivor pools, you can do so by accessing your Commissioner Console and then Pool Settings. Next, click on Pick and Scoring Settings and in the Pool Starting Week setting, you can select which week your pool will start.
If you are looking for Tie Breaker ideas for your Survivor pool, check out this article.