I'll start out by asking you a question: How do you know that you struggle with all the things you say you struggle with? Do you enter tournaments, or are you comparing yourself to Snakes you watch on Youtube? Do you compare your success in PM to your success in Smash 4? Having a healthy frame of mind is very important for this game, and if you're setting unreasonable goals for yourself you're gonna end up frustrated eventually. If that's all well and good and you really are just aware of your inexperience and want to work through it: Read the posts in these forums, particularly those from myself, Professor Pro, BND, and LupinX. There's a massive wealth of knowledge already available here, and discussion and new perspectives only helps to improve that further. So don't just read and lurk, but also post and contribute; just be willing to be open to other interpretations and seek those interpretations out.
This all sounds kinda flippant but honestly: communication is fantastic for improvement. Outside that, you can only practice so much on your own, and even when you play with others, unless they're communicating with you explicitly, it's hard to figure out where to go next. So be vocal as well in your interactions at smashfests, tournaments, chill days with your buds, what have you. I had an experience recently where I played with two HM Melee players in Michigan for around 4 hours. They didn't say more than two sentences to me about my gameplay. I started out doing pretty decently, taking every few sets. But eventually it just felt like they adapted to my gameplay and I had no idea what I was supposed to be doing anymore. It frustrated me a lot and I really don't enjoy those sorts of situations. So don't put yourself or others into those scenarios: call them out on their silence!
Invest in stream equipment if you can afford spending ~$150 (assuming you already have a CPU able to handle it—not that hard really) or find someone that does and make use of it. My setup cost less than $150 and as soon as my splitter cables come in the mail I'll be able to better substantiate their value, but trust me, it's not that costly. Share these videos with the forums so that we may pinpoint exact problems with your gameplay at present and so that you can also view your successes and problems second-hand. It's extremely helpful to be able to watch yourself because you'll notice things in review that you hadn't realized or remembered happened in the moment.
Additionally, practice. Practice constantly and learn constantly. Any time you pick up the game, practice. This can mean tech skill drills in your bedroom or it can mean developing matchup concepts while playing with your friends. Don't autopilot. Don't get lost in the game. Pay attention and interact with your opponent on every level. Do things differently and explore what works and doesn't work: Project M is less forgiving than Smash 4 in this regard I'm sure, but it's still very applicable—I spent my entire first year just playing things by ear and I've done decently well. I've just reached the point where I have to figure out concrete, solid plans to progress further, which is where the real work begins.
Snake is an amazing character with a lot of stuff going on. I'm glad to see a new face picking him up
