Hi, I was wondering if there is any way i can create something using blueprints that will allow me to mark an object like a cube for teleportation (and remove the mark again) using ingame keyboard inputs
Yes. What kind of Mark are you thinking of, like a visible mark or just storing it in a variable?
Well, im really new to this sorta thing so just storing it would be a good start 
To clarify the goal is to create a mark (in the end a visible mark) of a sort that would teleport the player to chosen mark. An example of what the inputs could be is F1, F2, F3 and F4 for the teleportation, while applying would be Shift + F(1/2/3/4) and to remove mark: ALT + F(1/2/3/4)
And that case I would just create an actor blueprint very basic actor doesn’t have any other components doesn’t have to be visible, and when you want to place a marker, you spawn that actor at that location. Also, when you spawn it, set tags on it so that you make an array of size 1 which has a tag of one, two, three, or four. Then, when you want to teleport to it, do a get all actors with tag, using one, two, three, or four. The Returned array should contain only the marker you want, as long as you destroy the one that has the matching tag each time you create a new one or teleported to the new location.