Just turned 18 and don’t know what to do with my CTF ( child trust fund )

Just turned 18 and got a letter in the posts stating my CTF is now available for me to withdraw or let it roll over into their ISA account or an ISA account of my choice. I’ve also started learning how to invest crypto. Now I don’t know wether I should use this money ( £500 - £900) into a ISA account of my choice or invest into crypto , thing is I don’t know what ISA I should invest in and I’m not sure if I want to risk all that money as a beginner , any experienced people out there I am asking you to pointing me into the right direction ???????? or at least give me some recommendations on where I should start. I just don’t want it to sit there knowing I can make the best out of it . Side info - ( I’m a college student in the UK and employed )