There are a few ways to go about if you want to make a bot like this.
One way would be to find a working IRC bot that you can modify to do what you want. There are loads and loads of them out there.
An other way would be to program it yourself, either from scratch or using different existing tools/packages. In this case you need to be decently proficient with some programming language.
Check this help article for more info on connecting to the TMI.