@sadeenbakkar you can use both dhanyabad and shukriya. but 'aapka swagat hai' is used more often when welcoming someone in your house or something....I use 'kot bat nahi' more oftenly because it means "its okay you don't need to say thanks". And to be honest Indian people usually use the english 'thank you' and 'welcome' more
Dhanyawad- thank you, you are welcome- aapka swagat h but in actual we never reply like this because we have many lines according to the situation and we use them accordingly.
"Dhnyawaad" is Thank you. You can also say shukriya (like shukaran in Arabic) but it not an Hindi word, however people understand and use it. There ia no specific word for welcome in Hindi.