It may get you through some of college but there will be a point where it will hold you back.
DO NOT put an extension on this bass, it will not do much for the sound, and the cost will overshadow what you payed for initially.
The strings should be fine for a while, especially if you are a beginner, just focus on the instrument and learning it, not getting caught up in the extras.
There are going to be a few people on here who know me, and know I asked the same things. I've grown a lot musically and after the hard work I put in, I am getting into that stuff. Give it time and don't worry about it till you hit ~10,000 hours of practice logged