Our application stores the currently chosen type of item, which is selected with one of the three buttons placed on a frame below the canvas.

Clicking with the primary mouse button on the canvas triggers the handler that stores the position of the first corner of the new item, and once it is clicked again, it reads the value of the selected shape to conditionally draw the corresponding item:

import tkinter as tk
from functools import partial

class App(tk.Tk):
    shapes = ("rectangle", "oval", "arc")
    def __init__(self):
        super().__init__()
        self.title("Drawing standard items")

        self.start = None
        self.shape = None
        self.canvas = tk.Canvas(self, bg="white")
        frame = tk.Frame(self)
        for shape in self.shapes:
            btn = tk.Button(frame, text=shape.capitalize())
            btn.config(command=partial(self.set_selection, btn, shape))
            btn.pack(side=tk.LEFT, expand=True, fill=tk.BOTH)

        self.canvas.bind("<Button-1>", self.draw_item)
        self.canvas.pack()
        frame.pack(fill=tk.BOTH)

    def set_selection(self, widget, shape):
        for w in widget.master.winfo_children():
            w.config(relief=tk.RAISED)
        widget.config(relief=tk.SUNKEN)
        self.shape = shape

    def draw_item(self, event):
        x, y = event.x, event.y
        if not self.start:
            self.start = (x, y)
        else:
            x_origin, y_origin = self.start
            self.start = None
            bbox = (x_origin, y_origin, x, y)
            if self.shape == "rectangle":
                self.canvas.create_rectangle(*bbox, fill="blue",
                                             activefill="yellow")
            elif self.shape == "oval":
                self.canvas.create_oval(*bbox, fill="red",
                                        activefill="yellow")
            elif self.shape == "arc":
                self.canvas.create_arc(*bbox, fill="green",
                                       activefill="yellow")

if __name__ == "__main__":
    app = App()
    app.mainloop()