I have a phone line and am using a adsl 2+ router for my pc. Now I wish to install a new Tp-link adsl 2+ wireless router for my lap which is used upstairs. and I wish to connect this wireless router to the same phone line with another splitter. Is this possible?
Nope you can only run a single dsl connection on the wire... even if you could the ISP would want to charge you for a second internet connection.
If the wire you are using is good enough and you have at least 2 pair you may be able to run ethernet over it. Many houses used at least cat3 cable and most new houses today use cat5e or cat6 cable for phone wire. Only way to truly tell is to buy a couple the jacks from your local home improvement store and try it and see if you get lucky.
There are devices that will let you use telephone wire to extend a network...they basically run a private DSL over the wire but they cost a lot ($500 for a pair) because few people need or use this.
You may want to look at using powerline extenders or if you have coax cable MoCA type devices.
Of course you could just run some cat5e/cat6 cable