Help with the pen tool... in PS

Im not exactly sure if the pen tool is the right tool to use but I just can’t get the look I am going for. I basically just want to create a square but one of the sides I want to have a curved side, if that makes sens. I am having a little trouble describing it but i pretty much just want to konw of you can make an angle like the following:

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… just a right angle, and have the two points connect with a curve, (much like line designs). Pretty much I just want to know how to make a slope in PS.

Thanks

Mike

O and can you make the pen tool just draw a line and not fill in the inside of the arc. I want to make the outside of the arc fill in but I can’t figure it out. Thanks for any hlep.