@Kajal,
Use renderUI function to add input elements from server functions. For example -
Ex:
#ui function
tabPanel(
      title = "Team wise Stats",
        uiOutput("team_"),
        submitButton("Go"))
#server function 
server <- function(input,output) {
output$team_ = renderUI({ selectInput("team","Home Team",choices = unique(IPL %>% filter(season == input$season_team) %>% select(team1))) }) }