As we know during ghusl water should reach every part of body but my beard is too thick and coarse and it is very hard to get water to reach the skin under it so I just wash my beard from outside. is the ghusl valid? wht shld be intensity of istinshaq?some say to force water into nose upto the bone

Ustadh AbdulAziz al-Haqqan

With our modern showers I can not think of anything other than waswas that can lead you to focus on this in such a way. Just getting under the shower is sufficient and water reaches everything. Don't fall into waswas.