@sonusarath , you have to file an amended return on form 1040-NR then for the year 2018 --- Perhaps you have to use something like SprinTax or a tax professional ( familiar with international tax filing ). You need to submit the 1040-NR along with the already processed form 1040 for 2018 plus a letter explaining that this was a mistake on your part, etc. etc.
For 2019 , as I have mentioned above you are dual status but you can request to be treated as a resident for 2019 and thus file 1040 ( supported by TurboTax.
I do not believe 1040.com supports 1040-NR
