Load testing using Jmeter 5k users, website crashed-Collection of common programming errors

First of all I would recommend you to try to understand how many users are going to use your system to set clear test objectives.

These articles I find useful:

stress testing web applications with JMeter (Part 1)

stress testing web applications with JMeter (part 2)

After you’ve set up your testing goals clearly follow JMeter Performance Testing best practices steps.

Also I would recommend you to get acquainted with Load Testing Cloud – altentive cloud solution for running your .jmx tests instead of local run, which often associated with resource demand on your PC machine.