If I understand you correctly, the layout begins with only one staff, and later a Bass Clef staff is added below - right?

The way Finale works, is that you add the Bass Clef staff for all the measures in the entire document.

To connect the two staves with a bracket, add a staff group, and choose a bracket type (Staff Tool, look in the Staff menu).

Then, in Page View, hide the Bass Clef staff where it is empty (Staff Tool, look in the Staff menu).

The Bass Clef staff will still be visible everywhere in Scroll View.

In the Group Attributes, select the Bracket Option

Show Bracket If Group Contains Only One Staff

In the case of two-part layout in one staff, with overlapping parts, to show part progression move the upstem notes slightly to the right.

In that way it is clear that the stems do not include both notes:

To get an “incomplete” measure, use the Time Signature Tool:

I was referring to the fact that at the beginning there is a solo (Blank staff) that has 2 staffs in the treble clef and then there is a group of (Grand staff) and I didn't know how to make that Blank staff not to be a group to be Solo only in the treble clef without the bass clef.

I managed to do so I hope it's good..

To be able to hide the Bass Clef staff where it is empty, go to the Group Attributes,

In the pop up menu

When Hiding Empty Staves

choose the menu item

Hide Normally

I have another question 

I did a rehearsal "first and second end" and it works ok but when I do the second rehearsal I want it to jump from A. (point) to B. (point) which doesn't happen ...
I only skip from B. (point) from measure 25 but I want the second time to skip directly from measure 24 to 27.
Can this be done? If so please explain!

How did you create the repeat endings?

The desired repeat playback should be done automatically if you use utility in the Repeat menu:

First, select the three measures that are going to be the first ending.

Next: Repeat menu > Create First and Second Ending

It looks to me like you want to start the endings after the first beat in 24 and 27. I would include the first beat notes under your first ending, and add them to the first measure of the 2nd repeat in 27. Then, follow Peter's instructions.

PS It really isn't necessary to use layers 3 and 4 in the bass clef. You can use 1 and 2.

I agree the D and F (24) should be included in the first ending but there isn't enough time for it to be added to measure 27. It will need to be rewritten some way. I think keeping the D and F in measure 24's repeat makes more sense musically.

One more point Cristi, it looks like you used ties as slurs. You do have some legitimate ties in your piece but you also have some slurs.

Sorry, I did not notice the partial measure in the first ending.

It is standard practice that the measures in a first ending are complete measures (never partial measures).

It is indeed possible in Finale to create the layout shown in the attached graphic.

But like Mike and Ernest I would not recommend it.

An incomplete measure in a first ending is likely to cause trouble, and cost precious rehearsal time.

When in doubt, write it out.

When in doubt, write it out.

Love that!  Along with, "If you are early you are on time, if you are on time you are late!."