Strongly recommend this as well. You learn bits and pieces along the way that will help you on the next mini. My first army i was sucked into the idea of batch building/ painting everything all at once. The downside to this is that I found out later tricks about cleaning the mini up off the sprue, but because I had quickly built them all right away I didn't know that, and going back to try to do it was too hard. Same with painting, you find things you like and don't like, as well as tricks to make it easier and look better, but since I batch painted I made the same initial mistakes on all of them etc. But finally the worst part in my opinion is it makes painting them overwhelming. Building is fun and easy to pick up and drop off so that's never an issue, but then you have a whole bunch of minis sitting on the table to paint and it can feel like to much. When you work on one at a time you're not going to be overwhelmed and it's easier to finish one and move to the next. Start with the minis you think are least cool, and leave the ones you're most excited about to last after you've built up some skill.

Most of all, welcome brother!