That’s just a vent hose. I just run it forward and down and zip tie to the frame. Do not run that to the carbs. If you have coolant in your oil, your water pump seal is bad.
Alloy Boltz is a BansheeHQ sponsor. They have stainless bolt kits. Here's a link to all their Banshee stuff.
https://alloyboltz.com/product-category/import-motorcycle-kits/honda-import-bikes/yamaha-yfz350-banshee/
Here's a couple complete front end kits that would work just fine. I would opt for the LSR/Fox, but that's just me. Either one of these are going to be night and day difference from stock.
https://www.ebay.com/itm/382291709971?fits=Make%3AYamaha&hash=item59025c9013:g:kCoAAOSw58tjG7IU&amdata=enc%3AAQAIAAAA0PBD3S%2F9ppA0hjcwSdEFr48ZFwxUh1hx2fUnylQlNVkww%2BOqJb77iW0H6CLrJTMb1PfjtXkLBtoKpFgF38juESQhw%2FOQZbKMo8ISdiiUoY3emCIkszP2%2FFgp8BUohnL6221n8k3FKLn2lBFMxfG961JVqKcJQPeGx%2F3ZlxDq6dXx0FepqHBXLpSg%2FyvI6bliH5yLasQ2HW39Uhe82lwxJsyuS8YXw2LESKMz0NZhs8UUBCIqZrL%2BsWz3QFe1U7Xb7BinIPtAakW4ZNfVMguvSz8%3D|tkp%3ABk9SR8qLx_PuYg
https://www.ebay.com/itm/401713089274?fits=Make%3AYamaha&hash=item5d87f74afa:g:7lUAAOSwbVViArOD&amdata=enc%3AAQAIAAAA8BkWU5%2BXwoNuIBzBbOnlCCtqMu4sJ6Zoueym%2BrTatmG07cL1mo6xhb6QCf7K0Vk%2BicufbDH03LTC%2BFRZa0T8q25sYOAomYbPd2O91WSWJM%2FlmEUHt4XGJWpZwW1M460FmqI1tDWY74O1Wg26QyXWej5v3391ros%2BR022Dcp58ZU8Q9y82xOVamRW4Y%2BF6z%2B6g%2FNb1BFPiCDGLUmsoQVVCz8WBSjf5i2x19ZHqdCHFIz%2F7pKgGxvAcKukplLNlF2%2BirhywnwG7HHE5mo8gFVARquaA8vziU7GAybGCvMJk8NcLTfKz0FBxS2kaiR2yjnytg%3D%3D|tkp%3ABk9SR8yLx_PuYg