How do I combine these two buttons

im trying to combine the paypal button and the f.submit button but have no idea How to get there Is there any better suggestion `
<!-- Set up a container element for the button -->

<!-- Include the PayPal JavaScript SDK -->
<script src="https://www.paypal.com/sdk/js?client-id=sb&currency=USD"></script>

<script>
    // Render the PayPal button into #paypal-button-container
    paypal.Buttons({

        // Set up the transaction
        createOrder: function(data, actions) {
            return actions.order.create({
                purchase_units: [{
                    amount: {
                        value: '0.01'
                    }
                }]
            });
        },

        // Finalize the transaction
        onApprove: function(data, actions) {
            return actions.order.capture().then(function(details) {
                // Show a success message to the buyer
                alert('Transaction completed by ' + details.payer.name.given_name + '!');
            });
        }



    }).render('#paypal-button-container');
</script>

my orders controller :::
` def purchases
@orders = Order.all.where(buyer: current_user).order("created_at DESC")

end

def new
@order = Order.new
@listing = Listing.find(params[:listing_id])
end

def create
@order = Order.new(order_params)
@listing = Listing.find(params[:listing_id])
@seller = @listing.user

@order.listing_id = @listing.id
@order.buyer_id = current_user.id
@order.seller_id = @seller.id


respond_to do |format|
  if @order.save
    format.html { redirect_to root_url, notice: 'Order was successfully created.' }
    format.json { render :show, status: :created, location: @order }
  else
    format.html { render :new }
    format.json { render json: @order.errors, status: :unprocessable_entity }
  end
end

end

private

def set_order
  @order = Order.find(params[:id])
end


def order_params
  params.require(:order).permit(:address, :city, :state, :name ,:mobile ,:PinCode , :size)
end

def total
    total=order.listing.price.sum
end

end
`