My iPad is 10.3.3 os and shows no updates available. How can I get ipados14?

Do you have an iPad 4th gen by any chance?

If so, you don’t update, because you can’t. iOS 11 and later requires a 64 bit processor. iPadOS 13 and later requires at least 2gb RAM. None of which are requirements that your iPad meets.

Also, every iPad that supports iPadOS 14 supports 15, so if yours did, you’d have to go straight to iPadOS 15.

Which model do you have?

The list of compatible iPad models can be found here:

https://support.apple.com/en-gb/guide/ipad/ipad213a25b2/14.0/ipados/14.0