Shall I take the job or not?

I work ar Argos and have done for about 2 years and 4 months I enjoy it there and have progressed well since getting employed. I work on the jewellery bit and love it there. The team leader on jewellery I work with is sooooo good at his job knows everything and I look up to him and feel soo much better when hes there. The problem is he said hes looking to leave and if he does im next in line for the role im sure and I really dont know what to do because being trained on jewellery I cant even do watch links which is a service we do i have tried and tried been taught loads and just cant get the hang of it and i just feel i cant take a jewellery team leader role if im gunna have to ask other people to do links for me it wouldnt seem right and also it would be big boots to fill if the current team leader leaves i will never be as good as him.grrrr what do i say if they offer me the job i cant take it if i cant do links and dont know if i can cope with the pressure of filling in such big boots what do i do?