If you're brand new to Tekken, then I would suggest maybe picking up Tekken 6 or Tekken Tag 2 for cheap and practicing with one the returning characters that's already in Tekken 7.
But the best option (in my opinion) is to pick either Katarina or Claudio so you can try one of the new characters. Both of them are very fun to play with and very easy to pick up. With Claudio especially, you can just do very simple bnb combos easily.
For example, with Claudio you can do u/b+4, f+3, and then running 2. Only three moves you need to learn to chain a combo together and still get good enough damage out. THe first two moves would just look
like this and the third would just be his running right punch.