I fully agree with @feederflightaware for a new hobbyist to start with a low-cost basic setup, and builtup bit by bit.
The blue DVB-T dongle with small whip antenna linked by @feederflightaware is an ideal low-cost choice for a start. Just place the magnetic base antenna (supplied with Blue DVB-T) over a metallic food can made of irron/steel, and place it indoors near an outer wall or window. The iron food can will serve two purposes.
(1) The magnetic base of antenna will cling to the can and stay upright. Without this, the antenna will keep on falling.
(2) The metallic food can will act as ground-plane for the antenna, and will substantially improve it’s performance.
As a next step, you can build yourself at almost no cost a DIY Quick Spider from a 1 meter piece of ordinary coax like the one used for TV antenna or Satellite dish antenna.
QUICK SPIDER - No Soldering, No Connector
Three Easy DIY Antennas for Beginners
Finally you can purchase a commercial antenna, Flightaware ProStick Plus, Flightaware Filter, and good quality coax like LMR240 or LMR400.