Not able to manipulate Landscape

I am kind of lost, I am trying to begin building a landscape and everything is fine when I first set it up and it puts the grid out but then when I choose any tools and click anywhere to manipulate it nothing happens but the normal viewing controls…in everything I’ve read or watched it just seems everyone is just using their mouse to use the sculpting tools and such but I am not getting anything happening. Am I missing something. I’ve tried it with only a 7x7 and a 63x63, Using custom or provided materials and still nothing. any help would be appreciated thanks.

Have you tried holding down CTRL and left clicking the mouse?

CTRL! Thank you Ehamloptiran I knew I had to be missing a key. Just tried it and works perfectly, thank you again.