Here is the absolute minimum I would use, if required to do so, to shoot a wedding:
1) A main camera, with 2 cards, a 24-70 F2.8, a hotshoe mounted flash for bouncing when required, backup camera battery, spare memory cards
2) on my belt / person a 70-200 F2.8 IS
3) a battery pack for the flash and a backup flash on my belt
In my wedding bag, a backup emergency camera, a 24-105 in case either or both of your 2 main lenses broke or were stolen, a fast F1.4-1.8 35 or 50 prime for very low light reception situations and a spare flash (I want to be able to shoot a wedding from my spare bag if something happen to the equipment I'm carrying.
For you, given what you have posted about your landscape experience, here a few things:
1) People need directing - you are going to be in charge - if you aren't no one will and it won't work - so you are now in charge - the good thing is, besides the bride, everyone will listen to you because that is what is expected at a wedding - and if the groom and bride have appointed you, you basically get to do wtf you need to do as long as the bride has approved it - so do it - get the job done (but don't be an ASS - be polite - you are not the show - the bride and groom are the show)
2) the bride has paid for her dress, or her parents have, do not blow out the dress - if you have a bunch of white in the picture, you are going to have to pixel peep occasionally to check exposure so that her dress is properly exposed - if presented with a pale fair skinned blonde bride and a dark tanned groom wearing all black - the bride always wins
3) spend a few days looking at nothing but wedding pictures and pick 5-10 poses that you like and 'practice' in your mind setting these up pictures - directing the bride, groom and family will be necessary (you are in charge and weddings have schedules)
4) F2.8, F4, F8 (1 row, 2 rows, more than 2 rows) - focus on the bride's eye
5) watch a few video's on bounce flash and then practice mixing ambient and bounce flash how much ISO relative to correct ambient exposure and then how much FEC to get a good exposure without it looking like people have been flash bombed
6) some couples and individuals are very natural together, some are not - they are very wooden - sometimes with these types of people, simply showing them a few pictures on the back on the camera, to show them how they look, make a little change, more feedback and then they will get what looks good
7) where are you going to stand when people walking down isle, etc, etc, etc - i.e. what does the event space look like and what are your camera settings for when action type stuff is happening
8) take lots of pictures of all the little artsy things that the bride and groom have made for their day - use LR / PS and try and produce some artsy unique photos
9) if for whatever reason, the colours / exposure doesn't work out, or maybe you just don't like the picture, force the picture to b&w and see what you can create
10) old people, grand parents, uncles and aunts, people that may not always be around - search out these situations as the day / night happens and find these pictures for the couple
11) if you have a certain picture set up, you really have 2 to 3 pictures so take them all (a full body portrait, a tighter 3/4 portrait, and or a the same but landscape) - think of shooting wider to allow cropping also
12) if / when you are doing a full body that includes the bride, do NOT crop off or not include the entire dress - the dress is like a 3rd important person
13) drink water throughout the day, make sure you eat, avoid alcohol
14) if it looks like it is going to rain, go purchase a few large white umbrellas from the camera store
You can shoot an entire wedding with 1 camera, one lens and a good flash if you really know what you are doing. If I had that, and I was allowed to bring one other thing, I would ask for an exact second copy of everything so that if anything went wrong, I would be ok. That one camera would be a Canon 5D3/4 or Nikon 810/850 with a 24-70 F2.8.
Hockey and wedding photographer. Favourite camera / lens combos: a 1DX II with a Tamron 45 1.8 VC, an A7Rii with a Canon 24-70F2.8L II, and a 5DSR with a Tamron 85 1.8 VC. Every lens I own I strongly recommend [Canon (35Lii, 100L Macro, 24-70F2.8ii, 70-200F2.8ii, 100-400Lii), Tamron (45 1.8, 85 1.8), Sigma 24-105]. If there are better lenses out there let me know because I haven't found them.