NO. The purpose of completing your Lasting Power of Attorney forms now is to allow people to make decisions for you in the future, if you can no longer make them yourself. It does not mean that once you have completed your LPA forms your Attorneys take over making decisions for you.
If you make your Health and Care Decisions LPA, your attorney cannot make decisions unless you have lost mental capacity and cannot make them yourself.
However, this differs with the Financial Decisions LPA, which allows you to say whether you want your Attorney to act for you whilst you still have capacity. This will enable your Attorney to help you to manage your finances.