Praise the Lord! Oh give thanks to the Lord, for He is good; For His lovingkindness is everlasting. Psalm 106:1
God loves it when we recognize Him with thanksgiving. Thanking the Lord is a form of worship. It is a way of saying “God I recognize you have given this to me and I want to thank you.”
When God puts people in your path to help you, it is okay to say thank you or good job to that person. It is a way of showing appreciation for the help. Recognizing good work in people helps build them up and encourages them to continue.
It is important, however, to recognize that the ultimate praise should be given to God. God is the one that put that person in your path and you should take time to say thank you.