use normal command block for this code /summon wolf ~ ~1 ~ {Invulnerable:1, Tame:1, Owner:YourNameHere, CustomName:"\"WolfName\""}
use repeat command block for this code/effect give @e[type=wolf, name=WolfName] strength 999999 50 true
use repeat command block for this code /effect give @e[type=wolf, name=WolfName] speed 999999 2e
use chat for this code
/gamerule commandBlockOutput false