AVR Freaks

Good evening all. I'm trying to teach myself some serial communication via UART using pc terminal in ATMEL STUDIO and an ATMEGA 2560. so far i've been able to transmit and receive. and also transmitting a string. But now i would like to expand to receiving a string sent from the pc terminal, but i can't seem to figure out how to. If anyone here would be able to guide me in the right direction, it would be much appreciated.

/*
 * USART.c
 *
 * Created: 10/9/2019 8:59:47 PM
 * Author : Morten
 */ 

#include <stdio.h>
#include <avr/io.h>
#define fosc 16000000
#include <util/delay.h>
#include <avr/interrupt.h>
#define BAUD 19200
#define MYUBRR 103
//((fosc/8)/BAUD)-1

void USART_init(unsigned int ubrr)
{
    //full duplex
    UCSR0A=(1<<U2X0);
    //enable receiver and transmitter
    UCSR0B|=(1<<RXEN0)|(1<<TXEN0);
    //set frame format: 8 data bit og 1 stop bit
    UCSR0C|=(1<<UCSZ10)|(1<<UCSZ11);
    //set BAUD rate UBRR 103 for 19200.
    UBRR0H=(unsigned char)(ubrr>>8);
    UBRR0L=(unsigned char)ubrr;
}

void USART_Transmit(char tx)
{
    //venter på tom transmitter buffer
    while(!(UCSR0A &(1<<UDRE0)));
    //putter data ind i buffer og sender data
    UDR0=tx;
    
}

char USART_Receive(void)
{
    //venter på at data bliver modtaget
    while(!(UCSR0A & (1<<RXC0)));
    //hent og retuner modtaget data fra bufferen
    return UDR0;
    
}

//transmitter en string
void USART_Send_String(char *ptr)
{
    //kalder transmitfunktionen for hver byte i ptr
    while(*ptr !=0x00)
    {USART_Transmit(*ptr);
    ptr++;}
    
}

char ptr[]="Hej med dig!"; //string der skal sendes

int main(void)
{
           
        
    USART_init(MYUBRR);
    //USART_init(103);
    
    
    while (1) 
    {
    USART_Send_String(ptr);

    _delay_ms(5000);
    
        
    }
}