To build a good running foundation, I come to know that I have to increase my weekly mileage (by avoiding injury). I found that I should do most (90%) of my run as easy. Earlier, I use to push myself in every session to give my best time. But now, I started running with 7km/hour speed for 5km unlike earlier where I need to push my self every day to run with Average speed 11.5km/hour. My PB for 10k(56:43min used strava) and 5k outdoor(27:28 used strava) Gym(25:55min treadmill). Will my current easy speed help me to build the good foundation? How many days in a week should I run? Current weekly mileage is 30KM and I want to increase to 70KM by increase 10% each week.
Recovery runs are usually pitched at a Rate of Perceived Exhaustion or "RPE" instead of specific paces.
Most 2-3 day-per-week running plans split the exercises up over a week into:
Rest Easy Run Rest Training Run (Tempo/Fartlek/etc) Rest Rest Long Run (normal/progression/fast-finish).
As the programmes increase to 4 and 5 times a week usually all that is added is more mileage at the "easy run" end of the RPE scale by swapping out the rests with more easy runs.
These easy runs should feel good, leave you energised and generally be around the 3-5 mark on the RPE scale.
Personally I use a heart rate monitor to help me stay towards the lower-end of my heart rate zones. I have similar run stats to you and usually do my easy runs at around 6:30/km.
You need to just experiment, try 7 and if it is too easy, bump up to 6:45, 6:30 until you find a happy place.
Footnote: You are adding a lot of mileage on if you aim for 10% per week. I recommend you run for time, not distance, as you get more experienced you can run for longer and faster which will bring up your mileage more naturally.