What type of glass is the fossil blue ch 2446..

Fossil battery replacement sizes are usually a 2430 (CR2430), 371 (SR920SW), or 377 (SR626SW).
https://www.fossil.com/en-us/******/how-to-change-a-watch-battery

That sort of information doesn't exist. Watchmakers learn that stuff by experience. Put it in a box and send it back to Fossil under warranty/repair.

https://www.google.com/search?q=reassembly+instructions+for+this+fossil+blue+CH-2485

..

try this link below
https://www.fossil.com/content/dam/fossil/PDF/watchinstructions/Fossil_Watch_Instructions_EN_UK.pdf

try link below
https://www.fossil.com/content/dam/fossil/PDF/watchinstructions/Fossil_Watch_Instructions_EN_UK.pdf

See https://www.fossil.com/content/dam/fossil/PDF/watchinstructions/Fossil_Watch_Instructions_EN_US.pdf

The file is a compendium of instructions for a large number of Fossil movements, but it is unclertain which movements the model CH-2331 and CH-2698 watches use. However, movement OS10 (page 15) appears to be the only one that matches the dial layout, button layout and also has a date window as the CH-2331. The watch has a quartz analog mechanism and uses one SR927W 1.55-volt silver oxide button cell. Silver oxide cells have low current output, but very long shelf life, so if the stem is pulled out completely when the watch isn't being worn, the battery could last many years. Scan the instructions to match up the CH-2698 with a movement number. A good guess from examining photos of the face of a CH-2698 watch would be movements OS20 / FS00 or VD53.

Thank you for contacting FixYa.
You should be able to contact Fossil at following link for directions/manual to your watch.
http://www.fossil.com/en_US/shop/customer_care/static/fossil-warrantyRepairs.html
Best wishes. Jewel

This is will take a jeweler or watchmaker to fit with a new crystal.
1st take this watch to the point of purchase and see if they can assist you, sometimes they will surprise you and depending upon the age of the watch may replace.
2nd beyond that usually only independant jewelers will work with fossils, almost all chains will not allow their employees to even change batteries in a Fossil (they are easy to break).