Photoshop help

[MatthewTheTheif]

ok, i need some help, im trying to make a shirt/hoodie design for my parkour team/squad/group, w/e you wanna call it, and i need design ideas, and also i would like help designing my own.

i would like to get the celtic trinity knot like this one between the wings of a pheonix like this one but all in one color so it could be any single color i want, idk if there is a funtion like that on PS or not, but if anyone could help out, it'd be greatly appreciated