First include the sqlite file in your project. Then copy that file from bundle to documents directory as below and create Database method.

-(void)createDatabase{
    NSString *pathForDocumentDirectory =[self databasePath]; //define new path and put old path in new one
    
    if ([[NSFileManager defaultManager]fileExistsAtPath:pathForDocumentDirectory]) {
        return;
        
    }
    
    NSString *path = [[NSBundle mainBundle] pathForResource:@"myDatabase" ofType:@"sqlite"];
    NSLog(@"bundle path %@",path);
    
    NSLog(@"doc dir path %@",pathForDocumentDirectory);
    NSError *error;
    [[NSFileManager defaultManager] copyItemAtPath:path toPath:pathForDocumentDirectory error:&error];
    
    if (error) {
        NSLog(@"error while transferring file=> %@",error.localizedDescription);
    } else {
        NSLog(@"db file saved in documents");
    }
    
}

For Database path we can use below method.

-(NSString *)databasePath{


    //define the property of databasepath ,path start from zero.


    NSString *pathForDocumentDirectory=[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES)objectAtIndex:0];
    
    pathForDocumentDirectory=[pathForDocumentDirectory stringByAppendingPathComponent:@"myDatabase.sqlite"];  //add myDatabase in this, myDatabase is the database which we created
    
    return pathForDocumentDirectory; //got database path in pathForDocumentDirectory
    
}

By using below code we can save data in database.

-(BOOL)saveRecordsInDb {
    
    const char *databasePath = [self.databasePath UTF8String];  //convert db path in char formate
    
    if (sqlite3_open(databasePath, &database) == SQLITE_OK)  //open database
    {
        
        NSString *insertData = [NSString stringWithFormat:@"insert into myTable (firstName,lastName) values (\"%@\",\"%@\")",@"jaya",@"arti"]; //myTable is the table name having two columns first name and last name.
        
        const char *insert_stmt = [insertData UTF8String]; // converting insertData into char
        
        sqlite3_prepare_v2(database, insert_stmt,-1, &statement, NULL);//prepare statement
        
        BOOL success;
        
        if (sqlite3_step(statement) == SQLITE_DONE)//step is used for execution
        {
            success = YES;
        }
        else {
            success = NO;
        }
        
        sqlite3_reset(statement); //reset to value 0
        
        return success;
    }
    return NO;
}

If we want to fetch records then we can use following code. In below code we are printing fetched data.
 

-(NSArray *)getAllDetailsFromDb{
    
    const char *databasePath = [self.databasePath UTF8String]; //converting databasePath path into char
    
    NSMutableArray *resultArray = [NSMutableArray new];
    
    if (sqlite3_open(databasePath, &database) == SQLITE_OK)
    {
        
        NSString *getDetails = [NSString stringWithFormat:@"select * from myTable];
        
        const char * get_stmt = [getDetails UTF8String];//convert getDetails into char formate
        
        if (sqlite3_prepare_v2(database,
                               get_stmt, -1, &statement, NULL) == SQLITE_OK)//for connection
        {
            
            while (sqlite3_step(statement) == SQLITE_ROW)
            {
   //it will run values column by column so we have to write column 0 ,column1 and all.

               NSString *firstDetail = [[NSString alloc] initWithUTF8String:
                                   (const char *) sqlite3_column_text(statement, 0)];
                NSString *secondDetail = [[NSString alloc] initWithUTF8String:
                                   (const char *) sqlite3_column_text(statement, 1)];
                

                NSLog(@"checks are %@ %@ ",firstDetail,secondDetail);
                           
            }
            
            sqlite3_reset(statement);
        }
        
        else{
            NSLog(@"Not found");
            return nil;
        }
    }
    NSLog(@"%@",resultArray);
    return resultArray;
}