I got 5% battery health reduction within in one month now my phone’s battery health is 93%.so can you give any suggestions for this problem

Battery Health / Maximum Capacity at 93% indicates that the iPhone is about 7 months old. If your iPhone is older than 7 months, your battery is doing better than average.

So, how old is your iPhone 13?

There isn't much you can do to prevent your battery from degrading. However, you can try not letting your phone battery go lowing than 40% or higher than 80%. The sad truth about lithium-ion is that they have a lousy lifespan. My battery health is currently at 94% (it's been about 9 months) and I am already feeling the shorter battery. Having optimized charging is great, but the phone battery will still degrade.

At 7 months, your Battery Health should be at about 93%. The number might not decline at all for a few months, then suddenly decline the next month. This is normal.

Your battery is doing just fine.