In this context, you should use the uncountable "experience". Just simply say, "I have much experience with team work." It is incorrect to say "below sentences". You can only say "the sentences below". Just say, "Need your help with the sentences below." Go and join a proper English class. You need it.

Can you let me know whether below sentences are correct? 1. In the past, I have HAD many experiences working in 'a team'. = A team is singular, if you say teams, it means more than one. 2. can i say ' I have many experiences working in team settings.' ( any example sentence that i can include the word setting) = yes you can :) 3. one of teams that i would like to share with you today "is" a team which I involved in many of years ago. = "one of the teams" - 'i played in' 'worked in' it needs something like this. 'is' is in the perfect spot! = "a team which i was involved with many years ago". hope this helps