can i update my ipad mini 2.5

On the basis of information provided, I believe you have a first generation iPad mini - and not an iPad min2. This is a common error of perception.

A first generation iPad mini can only be updated to iOS 9.3.5 (WiFi Only models) or iOS 9.3.6 (WiFi & Cellular models).

Apple ended update support for first generation iPad mini in September 2016. An iPad mini1 cannot be updated to iOS 10 or later major versions of iOS, as the internal hardware does not meet the minimum technical requirements for new versions of iOS/iPadOS. This limitation cannot be bypassed - in addition to which, iPad mini is a 32-bit architecture device, whilst all recent versions of iOS/iPadOS are designed for 64-bit hardware platforms.

iPad mini2 and mini3 are similarly limited to iOS 12.4.8. For these models of iPad, Apple ended major update support in September 2019. Since then, there have only been “point” security updates.

iPad mini4 and the current mini5 both support iPadOS 14 - this being the current release.

If you have an older model iPad mini, you may wish to consider that compatible Apps for older iPad models are becoming difficult to find - as third-party developers are increasingly dropping support for older versions of iOS preceding iOS11/12/13. As older versions of Apps are removed from the Apple App Store, you’ll not be able to (re)download or install them - which may severely limit the usefulness and utility of your iPad if you should you need to reset or restore your iPad.

As such, if you want or need to access most current Apps, requiring more recent versions of iOS than your iPad can support, you’ll need to consider replacement of your iPad with a newer or current model.

I hope this insight and information provides helpful explanation as to your inability to update your iPad mini.