At the far right side of your friends list is where you'll find the game recommendation button on pc I believe. Don't think there is a recommendation button on mobile.
Better is to find someone you would like to have as a friend (usually from your neighborhood list if you are new), click on their portrait, then select "add friend" on the right side. If you are guild hopping, picking someone active in a guild you pass through is a good choice.
If a person declines your invite, don't stress over it, there are plenty of other good players out there. Picking someone who is active is key though, since they will motivate your buildings and visit your tavern.