A preprint is a version of a scientific manuscript posted on a public server prior to formal peer review. As soon as it's posted, your preprint becomes a permanent part of the scientific record, citable with its own unique DOI.
Check the submission guidelines of the journals to which you wish to submit your article. Some will still consider papers that have been published and pre-prints, some will not.
Hem C. Joshi as suggested by Rajkumar Rajendram you should check the author informations of the journal in which you want to publish your work. If everything goes wrong, they might regard the submitted manuscript as plagiarized from the preprint. Personally I se no good reason for posting preprints.
Under normal circumstances I would advise against publishing work as pre-prints. However work related to COVID-19 should be made available as soon as possible if it may improve outcomes.
Pre-print limits author's opportunity of manuscript submission except to those that have standing policy in favour of pre-print. From personal experience, there is not much benefit from a pre-print. However, Frank T. Edelmann is the best way to go. Author with pre-print manuscript should seek clarification from editor of the intended journal prior submission of manuscript for publication.