Training advice please!

The Time Trial Forum (English forum) is a great resource for all things about time trialing. Find it here: http://www.timetriallingforum.co.uk/

In a more complete answer to your question:
For such a short TT 6 minutes is easily doable. 5½ minutes would be a more aggressive goal - 5 minutes would be a stretch goal, but achievable in 3 years of so if you are dedicated, young, and reasonably athletic.
Really you should look for longer TTs - at least 10 miles and better 25 miles. Breaking the hour for 25 miles is a milestone for competent TTers.
The time trial forum has a lot of good training advice, but if you are new to cycling, then for the first year just ride your bike. Set some goals like “100 miles a week”; then completing a 60 mile or 100 mile ride; then increase your schedule to 150 miles a week, with one 2 or 3 hour ride. Join a cycling club - preferably one with a racing background. By the end of a year you will have accumulated enough fitness, experience and knowledge to transition to a more specific trading regimen, including periodization, intervals, etc. But for the first year, just ride your bike.
Most of all enjoy riding your bike. Good luck.

Hey there! When it comes to short time trials like the one you mentioned, aiming for a 6-minute finish is a great starting goal. If you're feeling ambitious, shooting for 5 and a half minutes is possible too. It may take around 3 years of dedication, youth, and athleticism to reach the 5-minute mark. However, I'd suggest trying longer TTs, like 10 or even 25 miles, as they offer a better challenge. Breaking the hour for a 25-mile ride is a milestone for skilled time trialists. If you're new to cycling, focus on building a solid foundation through consistent training for your first year. Feel free to check out the time trial forum for more helpful training tips. Keep pedaling! ‍♂️