How can I run a gif on Uboot

I wanna run a gif while uboot is running like splash screen. How can I achive that?

what platform are you using? U-boot splash screen support was deprecated years ago. If you are using a very old u-boot you can find the splash screen/partition support description here:
https://www.digi.com/resources/documentation/digidocs/PDFs/90001129.pdf
it doesn’t make sense to have splash screen support in u-boot in modern hardware because it would require an LCD support for u-boot and u-boot is so fast it is easier to add splash support to the kernel and it will be displayed in seconds.