Setting up being Appointee for first time UC claim - cannot see how to do it

I know that this forum does not officially advise on Appointeeships.
If a member could help me I would be very grateful. This is UC related. I am already an Appointee for PIP for my daughter.
I am delayed sending in a UC new claim for my daughter because I haven't been able to fathom out how to do it.
I created the online account but could not make progress because it was all about the Claim and not setting up to Appointee to be able to make the claim. After 4 weeks the online account expired.
I believe there is a process where they visit to home first to confirm identity and only then can the claim commence.
How is the process managed after they visit us to allow me to begin the online claim?
I have googled and cannot see how I initiate any of this.
I tried to phone them but all of the automated options require a claim being started and there was no option for my query.
It feels like a huge obstacle!
Daughter does not have any service involved to be able to help me.
I'm hoping someone on here can advise me through their own experience.

I've been through this so I set up the account in d's name but giving my contact details. I seem to remember there was an option of alerting them to you starting the claim on somebody's behalf at some point so I did that. They phoned me and again I stated d couldn't manage any of the claim and I was appointee for PIP. They arranged to come to the house for her ID check and at the same time made me appointee for UC as well (according to the lady who came here appointeeship isn't transferrable although I have heard that it has been accepted by other Job Centre staff.) It has been really straightforward and my experience of Job Centre staff has been positive throughout.

Thank you! That is good to hear! I will try again online. Or go the the job centre if I cannot do it. My daughter will not go with me to the JC.