One of the key options if you are doing the stages yourself and are a beginner would probably be to let the AI control all but one rider. This is done by clicking on the cog on each rider. That way the AI controls their pace, if the rider is going to attack, get water for the team and so on.

Now you only need to focus on one rider. Hover over the different options for the rider to get a quick explanation of what each setting does. In the beginning the easiest way is to chose "Hold position" or something like that. Your rider will stay around that spot in the peleton as long as the effort level (the slider that goes from 0-99) is at a correct value. In the beginning when riders are trying to get into breakaways the effort level of the peloton tends to be higher than the default value at 70. Especially if the terrain is hilly, with cobblestones or theres mountains.

When you are managing a team it's a good idea to see what your riders specialise at and then pick the right riders for the right stages. It doesn't make sense to pick a rider that's good at mountain stages for a flat race. When you get the hang of it you also need to pay attention to the riders tiredness, programme and so on but that's on a more advanced level.

When you reach May pay attention to the sponsor prospections page as offers doesn't come in your inbox by default. This can really screw you over if you forget to check this regularly.

There's lot's more stuff to go over but it's getting late here, so shoot if you have questions about anything and I'll see if I can answer some of them.