okay so i opened a demo account on Trading212.com so i could observe the charts and familiarise myself with whats going on but i can’t find the following pairings;
USD/EUR
USD/GBP
instead they only have
EUR/USD
GBP/USD
im probably getting this wrong but as a complete noob i thought that you bought the first currency and sold the second one… so surely they should have both currency pairings?
is anybody able to explain this to me?
No … they show it only one way round - and every broker does the same, with those: the Euro/Dollar pair is always listed as EUR/USD only, and the Pound/Dollar pair as GBP/USD only.
The only one I’ve ever seen listed “both ways round” (to my slight surprise) was EUR/GBP and GBP/EUR with some brokers.
No; you can do either.
If you want to sell the Pound and buy the Dollar, you open a short position on GBP/USD and if you want to buy the Pound and sell the Dollar, you open a long one. If you want to sell the Euro and buy the Dollar, you open a short position on EUR/USD and if you want to buy the Euro and sell the Dollar, you open a long one.
This page explains how it works: How to Make Money Trading Forex.
All these pages should answer your other, related questions: School of Pipsology | Learn Forex Trading/
And welcome to the forum. 
Thankyou very much