whats the difference between wado ryu , shotokan and shukokai karate?

Wado Ryu is has elements of Jujitsu/Aikido in its practice. In a way, you are learning Jujitsu and Karate at the same time.

Shotokan is a traditional style that focuses on long, hard, powerful strikes and blocks.

Shukokai is a newer style and appears to be an offshoot of Goju-ryu. Goju-ryu is a hard/soft style, and they practice kata such as Sanchin, which differentiate it from Shotokan which is just a hard style.

In my opinion, training Shotokan is the way to go, because they specialize on developing powerful strikes, and when you train, this is your main focus. It can be distracting to learn many things at one time. There are ways to introduce softness into Shotokan, but I think it was wise that they introduce it at the higher level katas.