Is there an easier way to print the tiled pages?

Easier than the method presented on this video?

https://youtu.be/i2OFr1pVxuA?si=2YagKaKSlertJJ-N

An easier way? Maybe. It depends on your needs. I regularly use that "print frame" method to export equally sized regions of a larger image.

I suspect that video was made before Inkscape introduced multi-page documents. You might want to check out the page tool. Scroll down through this link.
https://media.inkscape.org/media/doc/release_notes/1.2/Inkscape_1.2.html

I can not figure out how it is done from the link you shared.

Step 1) Can you simply tell the steps? (Which tiling the page equally to 12 A4 pages, 8 pages, 6 pages etc.)

Step 2) Can you share a youtube link to do this?

With the page tool you can set rectangular areas of your canvas to be printed in order. You can move and resize and re-order the pages to be printed. This works well with pdf output via [File > Save a Copy] [Portable Document Format (*.pdf)].

When I click Pages Tool then Plus Icon you presented It just creates a new A4 page next to the original one.

So how do I split my original canvas including vectoral drawing into 12 a4 sizes?

Could you tell me in details please? (I couldn’t find a video including Pages Tool for this purpose.)

To create 12 A4 pages, choose the A4 page size and click [New Page] 11 times. [right-click] the page outline to Add/Delete/Move pages on the canvas

[click] the page outline and move it anywhere on your canvas. If snapping is turned on, the page corners can be aligned perfectly. At the right of the page toolbar, there's an option to [Move Objects with Page]. Turn this off to move only the page outline, leaving objects on the canvas in place. Turn it on to move objects with the page.

I created A4 pages with Pages Tool.

Now I do not understand what do I move to where?

A) Canvas To The A4 Pages Which Created With Pages Tool?

B) A4 Pages Which Created With Pages Tool to The Canvas

??

Both do no work. actually.

I Shared the file I created.

???

You're almost there. Your canvas has six A4 pages. Page 1 contains 12 rectangles, a group and 11 clones of that group. The remaining pages are empty.

I think this is what you want. I added more pages to the canvas and arranged them in a 4x3 grid. I stretched the shapes to fit across all the pages. For clarity, I changed the stroke colour and thickness. (Stretching the group distorted the line thickness.)

1. After I attach the A4 Pages created with the Pages Tool each other with snap tool I can not move them. How do I do It?

You can check the file I shared.

2. Based on the file you shared how do I print each numbered boxes as A4 separately?

Rearrange your pages with the Page tool. Here's a link to a screen recording.
https://imgur.com/a/zEqML1X

[File > Save a Copy...] then choose [pdf] as the file type to create a multipage document. Use your favourite pdf viewer to print it.