some random thoughts that may reinforce what you've been told already
school advice on medical careers can be very good - or pretty inaccurate. They rarely seem to know how much can change from year to year.
University websites will tell you minimum requirements but not what they actually take - the standard is higher than they say.
The Student Room website is not prefect but it's one of the most up to date sources.
No-one should be pushed into medicine, it's a hard life.
Encourage them to earn as much as possible before they start - it's a long course and when non-medical friends graduate your child will want to do things with them.
Try not to be ill at the beginning of August, it's when the new doctors start.
All medical schools offer interesting opportunities outside the course. I wish I could say what mine has done but it would be far too identifying. Taking some of the opportunities available will help them decide what specialty might appeal.
It is sensible to get involved in research early on if they may have any interest in academic medicine.
Students are frequently weak on medical ethics. Ethics questions appear at most, possibly all, interviews. They should study this guidance www.gmc-uk.org/ethical-guidance