Finding duplicates on separate sheets

Hi guys

this is my 1st post, ive always loved excel and belive im ok at it for self learnt but this one is testing me so im calling on some assistance if at all possible

I cannot actually upload my own spreadsheet as its over 1000KB so ive deleted most of it a made a mini version attached

what im looking for help with is:
1.) if any product code is selected on the kit sheet (Green tab) the same code on the catalogue (Yellow tab) would highlight so we know at a glance which products are being used and which are surplus
, one other issue is that the tabs have some code to change the name automatically to marry up to the kit name choosen

2.) as we have so many products in our main spreadsheet (not Mini) you will see the data validation drop down on the (Green Tab) are very long, i wondering if there is a way to hide some of the cells in the catalogue that also reduces the amount avaiable in the drop down list making it easier & quicker to make a selection?

or
is there a way to instead of drop down to start typing "Running outlet" for example in the cell and it only shows any line with that selected text to choose from?


any help be much appriciated