Minimum connection time is 45mins and Doha was built from the ground up for transit as this is what 90% of passengers do in Doha, supporting Qatar's spoke and hub operation.

At 1h45 you can assume you can have some time in duty free or the lounges, whatever takes your fancy. Depending on your mobility it can take 20ish minutes to get to the far end C / D / E gates from A / B gates and main lounges and duty free. Having a map of the airport can help orient yourself (there is one in the Doha airport app that doesn't need connectivity). Enjoy your flight and transit.