It should say on the unit entry in the handbook how many lectures / tutes are required
Some lectures, if they're longer than 2 hours, will be split into two or even 3 parts.
For example,
Lecture/01-P2 means lecture group 1, part 2.
Lecture/02-P1 means lecture group 2, part 1.
You have to go to both halves of the same lecture group - so say you choose lecture group 1, you have to make sure you can attend both Lecture/01-P1 and Lecture/01-P2.
If you see for example Lecture/01 (i.e. without the P1 P2 etc.) it means that's the entire lecture - you won't need to go to 2 parts - those are usually the 1 hour or 1.5 hour lectures (you lucky bastard).
Usually you only have to attend one tutorial, they just give you a lot of options for when you want to do it. Tutorial/xx just indicates the number of the tutorial group. You should only have to pick one.