The video guides by Jayour are good for level training and learning what is coming up next.
I would add the following tips to easily clear this on veteran:
1. For up close enemies switch to your automatic (rapid fire weapon). This is also good to use when first entering buildings so you can easily mow down enemies or once they run out if you have used a grenade.
2. Use single shot weapons when getting into outdoor scenarios or when you are up against far range stationary enemies. Pick them off one by one and slowly advance to new cover so you can pick off more enemies.
3. Your comrades will rarely help you out of a bind and at times it feels like you are single-handedly fighting the Germans, but make sure that you keep pace with them. If you see them running ahead then join up and progress in the level. Don't get stuck in a place forever even if going slow or the level will drag on for eternity and wear you down.
4. The toughest part of this mission for me was when you get the sniper rifle and the Germans storm your location (repulse the German attack). I found the easiest way to advance was to ditch the sniper and just use your rapid fire automatic weapon. The videos provided by Jayour don't show the easiest way in my opinion. If you get in the house quicker you get some breathing time before the attack starts. Then station yourself at the left window and focus on the trench where the Germans run down. Gun the rushing Germans and run away from grenades (if they are able to throw any at you before you can shoot them down).