I had a job interview, and I didn’t lie on my resume but when they asked me a question regarding my experience , I made up my own story about it and I realized after the interview with that what I did was wrong. Now this would not impact my oppurtunity as I had already gotten the job confirmation. Is the income I make from this job Halal?

It depends on your statement. If it's related to your qualifications and your job's nature is based on your qualifications then you are legally not entitled to aquire that job and in that case your job it self will not be legal.
But if your wrong information is different then you have done gunah but your job is ok.