I was very much like you, a serial restarter who sometimes got as far as grandchildren.
The first generational challenge I tried was a
Wishacy, basically you do as your sim wishes as much as possible and big events like romance or babies can only happen if they wish for it, I had great fun with this and did stuff I would never normally do just because they wished for it, like the founder having two romantic interests, marrying one of them, then trying for baby with both men, I had no clue who the dad was till the affair showed up at the hospital, talk about drama

He even came home with them in the taxi, needless to say that ended in divorce.
For me it was good starter to trying the dynasty challenges here which before I found a little daunting but it's true once you get going it seems far less complicated, I'm currently five generations into my umpteenth immortal attempt and hoping to finish it this time.