If you grow peppers from seeds or probably about any plant you are likely to get some helmet heads sometimes. This is when the seed is stuck on the cotyledons. Normally and ideally the seed coat will remain under the soil as the seedling grows out of it. Sometimes though they are stuck.
There is a few things that can help some with this but no guarantees. Soaking the seeds for a day or more before planting seems to help some. It gets the seed thoroughly wet and can soften it a bit. Planting a little deeper maybe around 3/8 to 1/2 an inch can help. To deep though can have other adverse effects if the seedling is to deep to emerge from the soil. Packing the surface of the soil down a bit. If it is too loose it may not provide any resistance to help pull the seed coat off the seedling.
It seems though no matter what steps I take there is always some helmet heads every year. Some people start surgery techniques immediately. I used to do this also. This can be tricky and for me was 50/50 at best on saving the plant. What I do now is nothing at least initially. I have found that most helmet heads will virtually grow out of the seed coat or at least grow out to a point that it is easier to remove. This sometimes takes a week or more and sometimes it doesn't work. I find that probably 80% ore more of the helmet heads will continue to grow and eventually either completely push off the seed coat or at least push it off far enough to make removal easier. I never broke out any tweezers, clippers, knives or other tools this year at all and lost very few helmet heads. In reality the percentage lost was probably less than 5 percent out of probably 50+ helmet heads.
Here is a seedling that was a helmet head when it emerged. As you can see now it has almost worked the seed casing off. It is now easy to remove safely. Often at this point you can pull it off or at the worst it will trim off the very ends of the cotyledons.
Here is the seedling from the previous picture with the seed removed.
Here you can see there were a few helmet heads but they needed no assistance. The seeds are just laying on the soil after they fell off naturally.
The next 3 pictures show more helmet heads that will either fall off eventually or be very easy to remove if needed.