I won the lottery and want to know how to best invest it

I find it really awkward and almost embarrassing to talk about this but I won the lottery nearly a year ago and I still have not done anything significant except take my sisters and mum on holiday.

I've accrued a nice amount of interest which I am also not doing anything with. I still do my regular job and I don't want to quit which I guess has made it harder to actually invest the money. I considered property investing but I wouldn't even know where to start. We grew up fairly working class borderline underclass and I just feel so scared that if I start spending the money it will all be gone soon.

Thanks for any advice