This is not a one-and-done and like many things, practice makes perfect.
Your child’s immune system needs regular training through the early years to be sure it learns to tolerate the foods long-term. The LEAP patients who were fed peanut multiple times for 5 years developed the most protection.
It may seem overwhelming to keep it up for 5 years and that's ok. Focus on getting these foods in regularly the first year of life when it is most important. Then aim for 6 months at a time and you may be surprised how far you get. Even if you don’t quite make it to 5 years, know that every bit counts and will make a difference for your child.