Tourist Visa From UK

I’m visiting China this year (2025), from the UK.

Fly to Beijing, train to Shanghai, and flying to HK.

I’m in Beijing for 4 days, Shanghai 4 days and then fly to HK.

Return journey is HK flight to Shanghai, then back to Manchester.

I’m aware of tourist visa for 10 days.

My questions are.

1. Do I have to apply for tourist visa before I go?
2. I’m ok to fly back into China from HK