An Introductory to New Player on understanding the general information about A Mission[helldivers.wiki.gg].

Note: There are official term and category for each mission type but these are just my layman term for them for easy understanding.
In these type of mission, you go from location to location doing objective[helldivers.fandom.com] and the enemies are just obstacle.

• Technical: Input stuff on a computer terminal
  
• Transport: Carry item from one location to another
  
• Demolition: Destroying Structure
  
• Physical Labor: Manually do stuff such as pulling lever or turning knob

These type of mission involve Wave of Enemies when the mission are active until the objective are complete.

• Semi-Defense Mission: Similar to General Mission, you have to go the objective but when you activate the objective. Wave of Enemies will swarm your location until the objective are complete.
  
• Defense Mission: Just defend from wave of enemies until your objective are complete and prevent the enemies from destroying your objective.

Just kill the Enemies

• High Priority Target: Introduction to an Elite Enemy on a lower difficulty.
  
• Exterminate: Kill a large group of enemies

1: The Planet
2: Active Players on that planet at your current time
3: Select your difficulty; must unlock lower difficulty for next difficulty.
4: Available "Sample" on that difficulty level
5: Current "Major Order", What the GAME Master want us to do in it story
6: Personal Order (daily order), thing to do for reward
7: Active Players in the sector at your current time
1: The Condition of the planet and/or Debuff of the Operation
2: The weather condition of the planet
3: The Debuff for the Operation; these only appear on higher difficulty level
4: The selected Operation
5: What kind of missions are within that Operation
1: Select Your Stratagems[helldivers.fandom.com]
2: Select Your Boosters[helldivers.fandom.com] (unlock and purchase in warbond[helldivers.fandom.com])
3: Change Your Gear
----------------------------
A: Select Your Helmet
B: Select Your Armor
C: Select Your Cape
D: Select Your Primary
E: Select Your Sidearms
F: Select Your Grenades

1: Current Health Point and Weapon on hand
2: Current Difficulty Level
3: Timer (For Your Stratagems & Reinforcements to be Available)
4: Possible Resource on the map
5: Current Objective
6: Mini Map
A: Current location on the map.
B: Orange Icon; current objective
C: Final objective
D: Extraction Point
E: Red Area; Enemies Structure and/or Enemies Present
F: Blue Icon; Tactical Objective/Side Objectives