One question...

Theme: Package, component in PCB

How can I add card edge fingers? (card edge connector, slot connector)
I want a PCB to create card edge fingers for an expansion card to be inserted into an expansion slot.

Search for the word "slot" in the TARGET component browser. Maybe your card edge slot connector is already available.

Otherwise you have to create your card edge slot connector as a component. Start with the PCB view. Place the pads on both sides and draw the edge of the PCB in that area or the complete outline of the PCB on layer 23 = PCB outline. Use straight lines and arcs for the construction. The PCB outline has to be a closed polyline at the very end.

Maybe you can add a rectangle into the bottom and top gold layers across all pads to have the fingers gold plated. Select all and press key [x] to export the "package". Now you create a connector symbol with the respective number of pins for the schematic view. Export it as well and thus generate a component of both by assining the right "package".

For creating components in general, look here. For rounding corners look here.