After creating a contract instance, you can execute the contract's methods.

Use call to execute a pure or view smart contract method.
Use send to execute a non-pure or modify smart contract method.
Please refer to, method.send().

There are two ways to create a contract instance:

//Example 1
let abi = [...];       
let instance = await tronWeb.contract(abi,'contractAddress'); 

//Example 2
let instance = await'contractAddress');