To add to the points above - the NDA you signed with potential client A can’t prevent you from discussing new information with potential client B that was not disclosed as proprietary with potential client A. Topics covered under NDA’s tend to be broad but only proprietary information shared by potential client A (information not commonly known in the industry) is secured under the agreement - you can talk shop, talk general category information, talk experience, etc. with potential client B, just not the specific new &/or proprietary information that was shared with you under the agreement.
For time-limits, we prefer to push for 24 months at most - the world is operating much faster than it was 10 years ago…and I agree with all who recommended reading the entire document - if you have any questions about particulars, get answers from someone qualified to give them.