can i get splitview in my ipad ios air4 in potrait mode with horizonatal

Contributors within the Apple Support Community (ASC) are all end-users, just like you. Other than the site Moderators, Apple neither monitor nor participate within the Support Community. As such, contributors have absolutely no influence with Apple or its Development Team.

ASC is a user-to-user technical community. We can offer advice with operation of your devices - and guidance/help if you are experiencing difficulties. We can also direct you to technical resources and appropriate contact-points for Apple support.

As such, given that you appear to have a feature request - the most appropriate channel through which to communicate your request is the Apple Product Feedback portal. For iPad and iPadOS, this can be accessed here:

Feedback - iPad - Apple

While you are perhaps unlikely to receive an individual reply, we understand that all feedback is both logged and forwarded to the relevant Apple Team(s).

I hope this clarification proves to be helpful to you.

iPadOS multitasking supports split-screen in Landscape screen orientation only. You’ll perhaps note that the individual App windows, in side-by-side view, are equivalent condensed “mobile” portrait view that you would see when using an iPhone.

While iPadOS multitasking does support slide-over view in Portrait screen orientation, split-screen is not supported.

Apple do invite submission of comments and feature requests via its Product Feedback portal. For iPad and iPadOS:

Feedback - iPad - Apple

You are very welcome. Perhaps, if a sufficient number of similar requests are received, the ability to use split screen in Portrait orientation will appear in a future update.