How to widen my wordpress theme?

Good day people. I just started a new technology blog www.clicktechblog.com and I want to know what can I do to improve it. I am new to web developing and I need your expert advice. First, I want to widen my theme and secondly I want my fonts to be bigger on all post. Also, I need some advice on how to build a decent homepage because I am not satisfy with mine. Kindly, let me know what you think and how I can improve it?