check out my VIDEO about your case, if you haven’t already. We all started somewhere…
Audio interface is important if you want to improve in whatever you are doing with audio. So it should be on your list. Your speakers and headphones will instantly sound better and clearer, than using your jack input. That’s what I have said in the video as well. So the quick answer is “Yes, you NEED one!”.
In almost every case the rule that “the more money you spend, the better the product will be”…applies to audio technology (in most cases). In every money-class you can find something that will work for you. However, audio interfaces are definied by two aspects.
How many inputs and ouputs
What connection: USB, Thunderbolt, etc.
The more inputs you have, the more it will cost. So you need to decide for yourself how many instruments (live) you want to record at the same time. 2, 4, 8…
You pay the price for the connection speed as well. Thunderbolt 3 is obviously the fastest connection at the moment, so the most expensive one. The speed is responsible for so called “latency”, meaning that you hear less “echo” effect on your voice or instrument during recording.
Interfaces you can look at: Focusrite Scarlett Series, RME Baby Face, UAD is great, without a question, however, $$$. Presonus 192 Series is great as well. Payable.
They all do the same thing, record audio. One thing I would recommend checking out which of the devices has a good history for your computer system. If you use Mac, then you should have less problems in general with all of them. Windows depends always on the in-build components and audio drivers.
I use Mac, and never had big issues with all devices and companies. But if you want to do it right from the start, UAD Apollo Twin as Mikael has mentioned is the way to go.
But as I have said before, it depends on inputs first of all. And after you have answered that for yourself, you go from there.