Using tkinter, when I place my tree and buttons on the canvas why do they disappear?

below are my codes

when I place my tree and buttons on the root I can see them

import tkinter
from tkinter import ttk
from tkinter import *
root = tkinter.Tk()
root.geometry("1500x900")
root.title("Writer")
canvas = tkinter.Canvas(root, borderwidth=10)
frame = tkinter.Frame(canvas)
vsb = tkinter.Scrollbar(root, orient="vertical", command=canvas.yview)
canvas.configure(yscrollcommand=vsb.set)
canvas.pack(side="left", fill="both", expand=True)
canvas.create_window((0, 0), window=frame, anchor="nw")
frame.bind("<Configure>", lambda event, canvas=canvas: canvas.configure(scrollregion=canvas.bbox("all")))
def treeframe1(rows, df):
tree["columns"] = list(range(1, len(df.columns) + 1))
tree['show'] = 'headings'
tree['height'] = '45'
colnames = df.columns
tree.column(1, width=90, anchor='c')
tree.heading(1, text=colnames[0])
for i in range(2, len(df.columns) + 1):
tree.column(i, width=100, anchor='c')
tree.heading(i, text=colnames[i - 1])
for i in rows:
tree.insert('', 'end', values=i)
tree = ttk.Treeview(root, selectmode='browse', height='45')
tree.place(x=960 + 200 + 00, y=45, width=920)
vsb = ttk.Scrollbar(root, orient="vertical", command=tree.yview)
vsb.place(x=950 + 200 + 00, y=45, height=930)
tree.configure(yscrollcommand=vsb.set)
vsb = ttk.Scrollbar(root, orient="horizontal", command=tree.xview)
vsb.place(x=960 + 200 + 00, y=970, width=960)
tree.configure(xscrollcommand=vsb.set)
b1 = Button(root, text="dd1", width=15)
b1.place(x=650 + 200, y=465 + 200 - 600 + 5)
b2 = Button(root, text="dd2", width=15)
b2.place(x=650 + 200, y=515 + 200 - 600 + 5)
b3 = Button(root, text="dd3", width=15,)
b3.place(x=650 + 200, y=565 + 200 - 600 + 5)
root.mainloop()

but when I place them on the canvas (i.e. replacing the "root" with "frame") i dont see them. Why is that happening?

I am new to tkinter so if someone to modify the code to make it work that would be really helpful

The root of the problem is that you haven't given the frame a size, so it defaults to being one pixel. You are then using place to put the buttons in the frame, and place won't cause the containing widget (frame) to resize to fit its children. So, the frame remains 1 pixel wide and 1 pixel tall.

You can easily see this by giving the frame an explicit width and height that is big enough to fill the space. For example, if you do canvas.create_window((0, 0), window=frame, anchor="nw", width=1100, height=1100) the buttons will appear.

You should use pack or grid instead of place to add the Buttons.

b1 = Button(frame, text="dd1", width=15)
b1.pack(padx=(850, 0), pady=(50, 0))
b2 = Button(frame, text="dd2", width=15)
b2.pack(padx=(850, 0), pady=(50, 0))
b3 = Button(frame, text="dd3", width=15)
b3.pack(padx=(850, 0), pady=(50, 0))

You can use padx and pady to adjust the location of the buttons on the Frame. I added arbitrary values to make it a similar location to your place values.