This is good way!
One of the things that touches the coastline, remember where you have active mountain building, subduction, or passivation on the outskirts.
Also, the movement of the plates affects the shape of the land. It can stretch or shrink. Remember that part of the land may disappear or appear due to tectonic activity. Therefore, it is not necessary to display all islands and island arcs within a supercontinent that have appeared relatively recently in geological time.
I understand you. The fjords and rugged coastline are always mesmerizing, but there are not many places on earth where such a relief can appear. This is most often associated with glaciers and rising ocean levels. Therefore, most likely fjords will come across starting from latitudes 45-50. (Here the values ​​can vary greatly from the settings of your world)




Gplates can help u construct correct models of ur world. It`s can be looks hard, but after some practice it will be easy.
Try check this and this themes.
https://worldbuildingpasta.blogspot....ch-part-v.html
https://worldbuildingpasta.blogspot....h-part-va.html
https://www.cartographersguild.com/s...ad.php?t=40045