My gate marks is 37 with a score of 459 in civil engineering (general category), what at its best can happen in this marks?

As per your score and previous year cutoff, the colleges you get in fourth round are:-

National Institute of Technology Agartala Department of Civil Engineering Water Resources Engineering

National Institute of Technology Agartala Department of Civil Engineering Environmental Engineering

National Institute of Technology Silchar Department of Civil Engineering Water Resources Engineering

National Institute of Technology Agartala Department of Civil Engineering Seismic Science and Engineering

Malaviya National Institute of Technology Jaipur Department of Civil Engineering Disaster Assessment and Mitigation

National Institute of Technology Manipur Department of Civil Engineering Environmental and Water Resources Engineering

National Institute of Technology Patna Department of Civil Engineering River Engineering

To know more about your chances of getting other colleges check out the PSU/college predictor link below:

https://engineering.careers360.com/gate-college-predictor