I feel that I am in another lockdown like Iwe once had during the pandemic. I feel that I am in another lockdown like we once had during the pandemic.

Since the lockdown was experienced by multiple people, I think it makes sense to say 'we'.

I feel that like I am in another lockdown like I once had experienced during the pandemic. I feel like I am in another lockdown like I once experienced during the pandemic.

Today is the last day I was inattended this training session. Today is the last day I attended this training session.

Today is the last day I wasam in this training session. Today is the last day I am in this training session.

The last few sentences of this post indicate that the session hadn’t yet concluded when you posted this, so “was” is inappropriate.

It lasted for four days from February 28thstarted on February 28th and lasted four days. It started on February 28th and lasted four days.

What you wrote isn't wrong, just it sounds a bit more natural with this word order.

After every Chinese communist party congress, government employees need to learn the spirit ofabsorb the key lessons from the congresses. After every Chinese communist party congress, government employees need to absorb the key lessons from the congresses.

"Learn about the spirit" doesn't quite work. I have done my best to find another translation, but I hope I haven't changed the meaning too much.

This training session is to train the spiritnecessary to spread the message of the 20th CPC congress and is held in a district party school. This training session is necessary to spread the message of the 20th CPC congress and is held in a district party school.

All the teachers are from a municipal party school and the central party school., All the teachers are from a municipal party school and the central party school,

Bbut the lessons given by teachers in the central party school are done by videos. but the lessons given by teachers in the central party school are done by video.

Ideally, try not to start a sentence with 'but'.

But the lessons given by teachers in the central party school are videos. But the lessons given by teachers in the central party school are videos.

The training timakes arplace from 8:30 to 11:30 in the morning, 2:30 to 5:30 in the afternoon, and 7:00 to 8:30 at night. The training takes place from 8:30 to 11:30 in the morning, 2:30 to 5:30 in the afternoon, and 7:00 to 8:30 at night.

[All trainees are notforbidden | No trainees are allowed] to leave the campus during the whole training period. [All trainees are forbidden | No trainees are allowed] to leave the campus during the whole training period.

Your original is OK but sounds unnatural to me.

I think no one really wants to attend this kind of training, but as government employees, they [have to / are obliged to]. I think no one really wants to attend this kind of training, but as government employees, they [have to / are obliged to].

'Are obliged to' is a more formal way of putting it.

Fortunately, the training will end bybe over at 4:30 this afternoon, and I can go home immediately afterwards. Fortunately, the training will be over at 4:30 this afternoon, and I can go home immediately afterwards.