I started a new job and I hate it

I started a new job at the start of September and it has been a giant step backwards career wise despite the title of manager. I am doing work that I would have done 4 years ago and had worked really hard to get to the point of wanting to go into management, do reporting etc. I changed job from working from home full time to 4 days a week in an office which don’t actually mind but there are a lot of things that outright seem odd

• hiring of siblings one since has left but sounds like a recipe for disaster
• after not having any really intro to the team I work in and what people do ( like not even any idea what their job titles are ) I asked my manager about putting meetings in to understand how the roles would work in conjunction with mine – and the response I got was is that because you don’t know what to do in your job
• varying hours – some people are allowed WFH days in the team, some people start at 6:30am though when I asked if they were happy for me to start 30 minutes early my boss said upper management wise it would not bode well for my career at said company but that he didn’t mind if I started early – the person who starts at 6:30 just started turning up at that time and didn’t give a shit what other people thought.
• there is a lot which I would class as my job role that I am not allowed to touch and basically everything I am being made to do isn’t in my job description hence the giant step backwards
• I also have not had any formal inductions around fire safety, the whole office chair desk height thing, nothing.

There are a few lovely people who I get on with well but feel like an outsider and that they company has made no effort to induct me. My notice is 3 months and I would feel like an arse handing it in a month in that I don’t know what to do. I thought pay day would make me feel better as it was a 25 percent pay rise on my previous role but it genuinely didn’t which realise that makes me sound awful but.

It also doesn’t help that I have been sick two days and requested a day at home after being sick as getting to and from work I genuinely wouldn’t have been up to it sitting in an office and more so not wanting to make the whole office sick.

I want to try and stick it out and fortunately I am on holiday soon for a few weeks but I also get the vibe if I did hand in my notice at any point they’d make my life a living hell. I don’t have a probation period either so I can’t just leave and also financially would only be able to cope until Xmas without a job.

Not sure what to do and just needed a giant vent.

Any advice would be great

Thanks