Okay, but the first thing that should come to your mind to do something similar in VFP is a container, not a form. Why did you go for forms immediately? You see a bunch of controls in a reserved free area. The designer of that old program should have used a pageframe, too, by the way, but he was likely using containers at that place, he made visible=.T. or .F. It's not a nice way also to design and maintain this. A pageframe also has it's pages at designtime and you can also switch between them to design and modify them. It's the simplest way to have a set of areas to display at the same place.
If you like the choices to be on the side, instead of the top, there are the pageframeproperties taborientation, where you can decide whether tabs are on the top (normal default), bottom, left or right, tabstretch, which determines whether you have a single row of tabs or - better in your case with the many options you have - multiple rows, and finally tabstyle, which determines whether tabs all have just the size necessary for the caption and there's free space after the last tab or whether the tabs always extend over the whole width or height of the pageframe and the captions are displayed justified within the tabs (each tab caption centered).
As others and I have also said, you could also use a pageframe with no tabs, just set the pageframe.tabs property .F. - and then have your radio buttons (in VFP an option group) to pick an option or a button group to have a staple of buttons looking like page tabs with their caption still horizontal (pageframe taborientations left and right have tabs with captions written vertically). So you could easily adapt to what you see there, but even with the argument the user acceptance is best when the new application just looks, feels, reacts and works exactly the same: Why even bother to recreate it then? You should improve what you're able to improve to more normal UI designs, like a pageframe is. If that gives you the idea to create forms and not even simply containers or - as most here got the same idea - a pageframe. It doesn't require to start a form and position it in a prereserved space, it consists of pages which are at the prereseved spaces, you can - if ou llike that for a start - have an empty page, too, then user pick a page by tab and that appears - without any code. It's exactly what you want and does not even require creating a container and place it there
Do you not knew the pageframe? What controls of VFP are you using regularly? No pageframe? No grid? No combobox, listbox? Too complicated? Take a look at a project called solution:
Code:
Modify Project (_samples+"solution\solution.pjx")
And then switch to the "Code" tab of the project manager (by the way, a good example of a pageframe you certainly know and use, too) and start main.prg with the Run button. Then ou can search and pick examples also about things like the VFP controls and how they work, with demonstration and source code (as the whole project source code is).