Super six is going down - how bad it is?

For the past three years(turned 27 this year), I have been working for an outsourcing company, and it just occurred to me that this was a very big mistake. I need advice on which way to go in my career.

A summary of my situation in points:

• I started working there as an SDR, my manager and mentor was the CEO himself, I did mostly outreach according to the predictable revenue book.
• This is a small private company - 30 people on board of which 90% are programmers. As it happens in such a company, everyone is responsible for many things and the development is as big as the skills of the founders.
• The pandemic hit and the bosses fired two other salesmen; I was left alone in sales; they offered me to help rebuild the company.
• My sales experience to this point: I was contacting 400 people a month (CEO, CTO); I didn't have any success in outreach but I was reliable, so that's probably why they left me; a few successes in inbound though.
• My boss went to make his own product; I was left alone and tried to carry all the sales in the company; As you can guess for two years I made mostly mistakes and nothing much developed;
• Why didn't I leave earlier? Because I was gullible, believed I would still learn, and had low self-esteem;
• The worst part was that during this time the company was happy with me, I was getting compliments, raises and bonuses; I thought I was doing a good job;
• This year I went to look for the next job; it turned out that my skills and the way I work are far from what is needed now; after 3 years I should be a senior BDS but I feel just like a regular/junior;
• I realized that my company never had a real and working sales and marketing department; I analyzed our sales and 90% are referrals or friends of the founders (these referrals are a bit standard in the industry but that's not what selling is about in my opinion - you should be able to get new customers)
• Why I think we don't have a good sales department:
• we use Hubspot but only to keep customer information there - zero automation with outreach tools, marketing or mailing,
• marketing is non-existent, we have our blog but zero campaigns and the company is again focusing on content writing,
• up to a maximum of 10 inbound prospects per month come to us - of which very few I manage to close,
• my boss is now betting on expanding account management and inbound sales - he does not believe in outreach so he wants to bet on referrals and inbound,
• I just realized that my boss struggled to sale before I joined the company and in his lifetime he successfully outreached and closed only one customer,
• we never had any targets - we just actively tried to develop sales - now I understand that my boss had no idea what to do, so he didn't push that way.

Summary:

• In my opinion, I have squandered the last 3 years blindly believing that the CEO of the company can teach me selling.
• I missed good leadership here, but also admit that I didn't explore the topic of sales too much myself - I knew nothing about business, market and selling so I was like a babe in the woods.
• I'm very angry with myself because I should be earning at least 50% more but I can't because I was blindsided. I am now in a huge depression and totally don't know what to do. I have lost all desire to make money, sell or live.
• Talking to salespeople, I can also see from myself that I have developed very bad sales habits through my lack of results:
• I keep notes poorly in CRM,
• I stopped working according to a daily schedule where there is time for everything, now I take tasks according to priority. There is no block of time for prospecting, writing to clients, etc.
• I don't have the strength for outreach because I don't believe I'll be able to get someone - that's why I'm delving into operational issues.
• English is my second language, I haven't had enough sales calls to be able to perfectly guide someone to a sale.
• As if you asked me now "if you can sell", I would answer - "I can try but the certainty that I will sell I do not have",
• I've now been "promoted" to account manager and am also doing inbound - however, I feel this is backsliding because I'm not actively acquiring customers, just waiting for the current ones to graciously buy more,
• I totally lost control of my skills, leverage in business and value.

Please help me but don't spare me, if I should give up selling then I will. However, be constructive in your comments. As for insulting and demeaning, I'm good at it for myself, so you don't have to demean me. ;).