Interesting to see such a specific question, because my first proper project (after learning different stitches by making myself a random sampler rectangle) was in fact a boat neck sweater! Specifically $5 in Paris by Anna Maliszewski (Ravelry link / designer site)

Really if you're ok with doing basic shaping like increases and decreases then something like this is fairly simple to follow. But I'd add an important caveat:

Despite this project going fine the first time round, I had to entirely frog it and remake the whole thing. Why? Because I literally just followed the pattern. I didn't know anything about how to adjust a pattern to fit MY body, and I have really wide hips with a short waist so it turns out that's important for me to know. Sometimes you can get lucky and find a sweater pattern designed for a body shape like your own, but a lot of the time you will need to be making adjustments here and there.

So I think it's that side of things rather than how complicated the patterns actually are, that can be a big problem for newbies. If that makes sense?

Even the second time round this didn't turn out to be super flattering anyway, but I did learn a lot and it was made from cheap yarn so no regrets. I guess the question is, are you the type to appreciate the learning experience or the type to freak out if it doesn't go perfectly right?

The style of the garment is not as important as the quality of the pattern, but that can be hard to ascertain (even with lots of experience) until you knit it!

A simple sweater is likely to involve just a few extra stitch types like increases and decreases, and some new techniques, like knitting in the round, picking up stitches, or neck shaping. All of these are quite simple in principle, and should be reasonably easy to get the hang of.

How these steps are described is a whole other story! I recently helped a friend with a very simple vest, but it was honestly one of the most confusing patterns I've ever read. And I've knit hundreds of things over 20 years!

So my advice is:

1. Stick with patterns with good reviews, written by a quality pattern maker, or at least is very popular (more chance any kinks have been worked out)

2. Read through the whole pattern before you begin and see if it makes sense.

3. Ask an experienced knitter if you get stuck! There's a good chance the problem isn't your skills but the pattern itself.

What's the pattern? I'd be happy to take a look and give my two cents.

Why not try socks? There are some good simple sock patterns out there. You’ll learn knitting in the round and other skills depending on whether you make a cuff down or toe up sock and there are lots of YouTube videos to follow along with.