'let's' is a contraction of 'let us' and is used as a first-person plural imperative verb. It's a way of making a suggestion or proposal, indicating that the speaker and the listener (or listeners) should do something together.
'let's' is used to make a suggestion or propose an action. It's always followed by the base form of a verb. It's informal and is more common in spoken English than in formal written English.
Let's go to the movies tonight.
Let's try that new restaurant downtown.
Let's not worry about it right now.
'let's' is often confused with 'lets' (without the apostrophe), which is the third-person singular form of the verb 'let' (e.g., 'She lets her dog out every morning'). Avoid using 'let's' in very formal contexts or academic writing. Instead, use phrases like 'we should' or 'we could.' Remember that 'let's' is always a suggestion for a group that includes the speaker. If you're making a suggestion for someone else, use 'let him,' 'let her,' 'let them,' etc.