F1 2021

Pretty easy achievement to get. From the Main Menu, tab over to Solo and go down to Grand Prix.
From here, select the F1 2021 cars, then select Britain, which is the 8th circuit in the calendar.
Either select Williams, McLaren, Aston Martin, Red Bull or Alpine and then whichever driver you please.

Under weekend structure, I changed it to One-Shot qualifying (which will get you closer to "1 Lap is all I need" achievement". I also changed session length to Very Short which means you only have to do 3 laps. Under Simulation Settings I had the AI difficulty set on low - but that is your personal preference.

Once that's all setup, start the session, grab pole and then the win!

Nice and simple and this is the same method for other-related achievements like this.

Really Easy Achievement

Obtained after winning a single player "Grand Prix" at Silverstone with a Williams, McLaren, Aston Martin, RedBull or Alpine. To do this, select the "Solo" category in the main menu and start the "Grand Prix" game mode there. The track "Silverstone" (Great Britain) and then any driver from one of the named teams must be selected in the driver selection.
The other settings (race distance, simulation options, AI difficulty and driving aids) can be selected as desired. The trophy is unlocked after winning the race.