I can't plug my Apple Pencil 1 with my iPad 10th generation

See:

Pair Apple Pencil with your iPad - Apple Support

The first generation Pencil is charged and paired from iPad10 using the iPad charging cable - and an Apple USB-C to Apple Pencil Adapter:

New first generation Pencils now ship with this special adapter in the box along with the Pencil. However, some older stock purchased from retailers may lack the USB-C to Lightning adapter - and may instead have an older Lightning to Lightning Adapter.

For owners of older first generation Pencils, or for “old stock” new Pencils, the new special adapter can be purchased directly from Apple as an accessory.

https://store.apple.com/xc/product/MQLU3ZM/A

The iPad 10th Gen has USB-C and the Apple Pencil 1st Gen uses Lightning. You need an adapter for the Apple Pencil to be able to work with iPad 10th Gen. This is the adapter that you need to be able to connect to your iPad. USB-C to Apple Pencil Adapter

Believe it or not, I just had the same problem and I tried using Light Blue, the app to force the connection and it didn't work. It would appear multiple times in the app (meaning it would recognize it but then it would disconnect and then see it again and so on) but giving me the " timeout interrogating the peripheral" message, and after reading post after post I read that a someone tried putting the pencil under the hair dryer for like 3 minutes to warm the battery up and that WORKED! Now it requested the pairing by itself immediately after connecting it. The battery is drained but I'm guessing the warm up helped kick the firmware up enough to connect and recognize the iPad. Now I'm charging it hoping the battery will last. Mind you, it's a brand new Apple Pencil 1st Generation with an iPad 10th generation.

Here's the light blue app solution: https://www.youtube.com/watch?app=desktop&v=E78rkv6kx0Q

Straight from the pencil website:

USB-C to Apple Pencil Adapter (required to pair and charge with 10th-generation iPad)