Pomoc oko JavaScripta

Pozdrav, Zanima me mozete li mi pomoci oko JS? Ukratko, radi se o par stvari. Radim preko platforme bigcommerce te bih trebala napraviti neke izmjene, a do JS ne znam kako doci, a i da dodem ne bih znala napisati kod. 1. Trebala bih da se napravi mogucnost narudzbi samo iznad 80 kuna, da se ispod 80 kuna ne moze naruciti. 2. Kada se u checkoutu odabere placanje pouzecem da se na iznos narudzbe nadoda 7 kuna. 3. Ovaj novi zakon sta se tice kuna i eura, trebala bih pored svakog iznosa u kunama(gdje god pisu kune na stranici) staviti i iznos u eurima. Taj iznos se treba zbrajati i sve isto kao i u kunama, takoder i u kosarici i checkoutu, mailovima, racunima itd. Puno hvala :) Lijep pozdrav Elena English: I wonder if you can help me with JS? In short, these are a few things. I work through the bigcommerce platform and I should make some changes, and I don't know how to get to JS, and even if I did, I wouldn't know how to write code. 1. I should make it possible to order only above 80 kuna, so that it is not possible to order below 80 kuna. 2. When cash on delivery is selected in the checkout, 7 kuna is added to the amount of the order. 3. This new law regarding kunas and euros, I should put next to each amount in kunas (wherever they write kunas on the page) the amount in euros. This amount should be added up in the same way as in kuna, also in the basket and checkout, emails, invoices, etc. Thank you very much :) Greetings Elena