I would not consider years a short period. But anyway I have started with around 50-65k. Don't remember exactly. Around 50k was inheritance. I knew about investing since I was a teenager. I was interested in trading futures because that's what was popular back then during my high school years. But I realized day-trading is just another day job, so I never got into it. And stocks, back then, were expensive(broker fees) and you needed a lot of money(thousands instead of hundreds) which was simply out of the question for a teenager. When I inherited the money, I wanted to tuck it away and preserve it but then I said to myself "F. it", I always thought about investing in stocks one day and there won't be any better time. So I started.And I found out the fees and complication were no longer such an issue like in the past. On the contrary, it was very easy and cheap. Slowly, with couple of thousands to get my feet wet and couple of months later, I invested all of it and my own money on top of it, as I gained confidence. And it was the best decision in my life. Mostly because it inherently provided the best financial, economic and geopolitical education no school could ever give you. And as I have said, I have been living off of my investments already. Since last year(I could have sooner but I had a great job). Sure, not all people inherit money to start with but that can be equalized by time(ie. start sooner with less). Also, it is a waiting game. You need patience. It's not get rich quick type of thing. And you learn along the way. You make mistakes and you learn from them. If you have 1000$, there is nothing stopping you but your fear of letting the money go(not lose, just not have access to it).
My bank is my broker. It's a local(non-US) bank so I cannot recommend it to the worldwide audience. I don't trade though so I don't use modern platforms where you can make a trade with one click. I just simply log into my account and manually place an order. I know that Interactive Brokers are one of the most popular international brokers so maybe give that one a go. And then I guess Lynx would be the second international broker people often mention. In the US, I guess Ameritrade or Schwab...I have no idea, I'm not versed nor qualified in that so you better ask someone else.
I am very lucky that my broker charges me insanely cheap fees - 7.95$ for up to 100 shares and 9.95$ for more than 100 shares per order. Since I usually do tens of thousands of shares per order, this saved me many thousands on fees throughout the years. Usually I think it is 0.02$ per share with most brokers. You can use brokers that use spread to avoid paying any fees but I would strongly discourage from those brokers and just pay the fees(spread is where you want to buy at $1.00 but the broker waits for 0.99$ and takes the fee of $0.01*number of shares and same if you want to sell).
As for sources of information, you have to find your own. I watch yahoo comment sections on stocks I am interested in and I am mostly on stocktwits. Not that you get much out of there(plenty of smoothbrains, like everywhere) but I like to keep myself up-to-date in case something goes down or someone has a good analysis to share(not very often). It simply keeps me engaged.
As for investing advice..I would highly recommend getting Phil Town's Rule #1 book. I haven't finished it after the years but it is VERY good for novice investors. It is written in very plain language, the advice is very defensive(safe investing) and the guy had humble beginnings so he went through the rough himself. He also has YT channel and podcast but that's up to you if you want to follow. But I drew inspiration from him, among others, for sure. Best thing to do is to look for creators and find the ones you resonate with and simply follow those. Each has different approach so you need to find the ones whose philosophy you like. Keep in mind that most of YT scene are people who have no idea about anything and just bullshit their audience. So be careful to not fall for that. It will take you time to filter out these people.
But I must warn you to avoid getting lost in theory. It's mostly just complete bullshit. The entire financial industry, especially investing, is based on making simple things as confusing as possible and selling people the lie that they cannot do it themselves. Investing is really as simple as basic math in elementary school. Heck, even pre-school. Once you start learning you'll see it's all just a bunch of grifters trying to profit on people's ignorance.
PS: be wary of any financial magazines/websites. For one, one day they write "sell" the other day, heck even hour, they write "buy". They are NOT reliable source of ANY information. Think about what they are in the first place - they need to cater to all people to get the views and clicks. So they will write whatever the audience wants. And for second, don't listen to any analysts or people giving investing advice for free. If they would be any good, they would not be analysts but rather invest themselves. Same goes for any courses, classes,... whatever. Those who know do, those who don't teach. It's 10000% true in investing. In the end, it is YOUR money and YOU have to make the decision. No one else.