Lifetime ISAs work differently and only allow you to save up to £4,000 a year in them.
This can come out of your £20,000 total ISA limit.
You are entitled to split the remaining £16,000 of your full ISA limit into another ISA account or several other ISAs.
Parents are also entitled to an additional £9,000 in Junior ISA accounts on top of this £20,000 ISA limit.
Junior ISAs work in the same way as adult stocks and shares ISAs and must be opened by parents on behalf of children.