I've already done some Googling and got the character viewer button on the menu bar of my Mac but I have no idea how to get the Stylistic and Titling alternative characters on either Photoshop or Word.

https://www.dafont.com/amerika-pro.font?text=JUNGLE&psize=l

Any advice would be massively appreciated!

Thanks

In Word, go to the Font dialog. Select the Advanced tab and from there you can select a Stylistic Set. There is no option for the titling feature.