iam able to program 700mhz channels in this scanner . But iam not able to hear them
As KE5BCP noted, while you may be able to program the 700MHz frequencies, you will not be able to hear those transmissions. All you'll hear will sound like static.
Take a look at the system previously linked:
Texas Wide Area Radio Network (TxWARN) (P25) Trunking System, Various, Texas - Scanner Frequencies
That's a digital system used by a number of agencies in your area. Your Pro-163 is not a digital scanner. It is analog only.
Additionally, Canton, in your county (Van Zandt) has received a license for 700MHz frequencies, authorized to be used for a trunked system: WQYB437 (CANTON, CITY OF) FCC Callsign Details
I don't know whether the new system will be used by Canton only, or also for other agencies, city & county, in the area. Also not known is whether this will be a standalone system, or linked into TxWARN P25. To receive either TxWARN P25, or the new frequencies licensed to Canton, you would need a digital scanner. No amount of programming would make your existing scanner, the Pro-163, work for these systems.