Well, I'd try reading the combat section slowly and try to keep to the simple things (like initiative, action types, movement, attack rolls, damage rolls) first, then if you think you got that, expand to the more complex stuff (like attacks of opportunity, special attacks, etc).
Here's a very simple example combat to see how the basics work:
Hero is a 2nd level Fighter with Str 14, Dex 14, Con 14; Hitpoints 20; wearing studded leather armor and a heavy wooden shield (Armor Class 17); armed with a longsword (Attack +4, Damage 1d8+2).
Villain is a 1st level Fighter with Str 12, Dex 12, Con 12; Hitpoints 11; wearing a chain shirt (Armor Class 15); armed with a battleaxe (Attack +2, Damage 1d8+1).
Hero enters room, where Villain is hiding. Hero spots Villain. Villain spots Hero. Combat begins. Hero is 20 ft. away from Villain.
Initiative. Hero 1d20+2=14, Villain 1d20+1=7.
First round.
Hero's turn. Hero takes a move action to get close to Villain and draw his sword during the move, and then a standard action to attack him. Attack 1d20+4=17. Hit. Damage 1d8+2=5.
Villain's turn. Villain takes a move action to draw his battleaxe and a standard action to attack Hero. Attack 1d20+2=13. Miss.
Second round.
Hero's turn. Hero takes a standard action to attack Villain again. Attack 1d20+4=15. Hit. Damage 1d8+2=7.
Villain is now at -1 Hitpoints and dying.
Hope this helps!
Bye
Thanee