In reply to calitouk:
Hi, don't underestimate how much harder carrying a full pack is if you aren't used to it. The walk on your suggested day one for instance is a full day with a big pack!
Maybe plan something a bit more compact and have opportunities to add bits? What about train to Penrith, bus to Pooley, launch to Howtown, then walk either the Beda Fell ridge to Boardale Hause (shorter) or Loadpot Hill, High Raise! Rest Dodd etc, but in both cases camp at Angle Tarn. There is a lovey wild campsite just on the back of the little causeway.
Day two down to Patterdale and Glenridding for supplies, then Helvellyn by one of the Edges. Head North along the main ridge picking up Whiteside, Raise etc. Look to camp just off one side of the ridge, depending on wind direction. If it's westerly there are viable sites in the valley above Greenside, ditto Deepdale. Don't try to use any of the Gills running west as descents! If you fancy a more comfortable night head to the campsite at the Kings Head Thirlspot!
Last day walk into Keswick, either by finishing the Dodds and Clough Head or lower and shorter over High and Low Riggs!
There are endless alternatives depending on how high, far, tough, easy etc you want to make it. Have fun!