Find service or tools keyword

I have Ahref, Semrush and UberSuggest. I am looking for a way to find the services or tools or SaaS applications with low competition keywords and easy to rank in Google.

Can anyone guide me, how can I research it? I know the way to find low competition keywords from affiliate websites using Ahref.

one way is checking which keywords your competition ranks for and steal them...
another way is to check which relevant keywords sites like reddit, quora, pinterest, linkedin rank for and steal those too...