Hello, I am new to the forum, hope everybody is ok

Need some advice please, I am looking to get a website started and I was wondering if :

1) It is ok to show various other companies info and contact details without their permission ?
It would hopefully be generating work for them so it would be in a very positive way.

2) Would I need to take out any type of insurance to cover myself for a classified listings website ?

Any advice would be helpful.

Thanks
Jamie