22 years old, looking for guidance/feedback on finances.

I think I work better as a person when I have a second opinion on things, so I was just wondering if anyone could give me their thoughts:

Graduated mid-2025. Managed to get a job in my field but very much on the ground floor. My wages are very poor (£23,600 a year) but this profession is very reliant on a workplace funding and supporting your training post-graduation.

I live with my dad and pay £300 a month. I am very well supported by family but have set up a modest emergency fund just in case.

I'm on track to have £4,000 in my Cash LISA by the end of the tax year. House prices are (compared to some places) low in my area and I'm hoping to be on the property ladder before 30.

I also have a S&S ISA with a small amount of money in an ETF. I plan to increase this, but it was mostly just to learn more about a S&S ISA and educate myself on the process.

My main monthly expenses are my rent, travel expenses, and a 9.99 subscription. I have £1000~ put aside for a holiday I've had planned for a couple years. I go out for food or beers twice a month maximum.

My questions are:

1. Is anything I'm doing wildly wrong?

2. As silly as it sounds - and I know it's hard to say without all the context - what's the best way to "seek out" opportunities for growth at work? Is it as simple as politely asking?

3. I plan to open up a high interest savings account. A friend of mine went to his bank in person and was offered much better interest rates than those listed online, do you think it's worth my time doing this or should I open an account with some of the highest interest options listed on Money Saving Expert?

4. I have quite a lot of old stuff I'd like to sell online. My dad also has a hell of a lot of stuff clogging up the house that he's said he's happy for me to get rid of and keep the money, so long as it makes the house tidier. Is there any tax on this should it exceed £1000 total? It's my understanding that if these are personal belongings not bought with the intention to resell, I should be fine, but how do I ensure whatever platform/HMRC know this?

5. Less of a question: does anyone have any more general advice for someone in my position?

Long post I know. If anyone finds the time to read this or reply, thank you!