### ecliptic curve find only x

sir,
im a pyhton programme and some idea of sagemath and c++ and .net
i study the btc cryptography seacp256k1

my problem is that
1. how to find x value where start from nearest of k so my loop is small and find the k
2.how to find cyclic ring where the repeate of x and ecliptic curve on seacp256k1 or bitcoin parameters
3.if i have x,y of public key and address how to find private key descrete logirithm problem loop is very large
how can i mage the small cuve , any apprelication or function if availabel in sagemath i required with baby step consider to proof