1. Guessing there is a rim strip in the rims now (you will need to either tape or use the Bontrager rim strip)
2. I prefer to stay away from proprietary stuff so, I would recommend tape (two tight wraps in the center will work fine)
3. Stans valves work great
4. I would consider a Panaracer Gravel King SK or Schwalbe G1 tire (Schwalbe will be easier to mount)
5. Don't forget sealant (I use Orange Seal but, Stans is good too)