It's not easy to answer this in nutshell but I will try my best and one should be familiar with terms like DNA ,chromosome ,centromere, chromtid.

Now generally there are 46 DNA molecules in a normal functioning cell which are present in form of chromatin thread in nucleus.

During S phase of interphase of either mitosis or meiosis the DNA got replicated and there are 92 DNA molecules now.

Since one chromtid represents one DNA in nondividing cell…here 92 DNA form 92 chromatids but these chromatids are joined together at centromere to form 46 chromosomes called as metaphasic chromosomes having four arms and two chromtid just like each other….

I hope this will help if not entirely then at least a little bit to make one understand the concept.

Thankyou.